Environmental Pollution Control

UNIT 1

1. Suspended solid present in the waste water generated in blast furnace gas cooling and cleaning
plant is removed by

a) biological oxygen pond.

b) radial settling tank (thickener) using coagulant (lime & ferrous sulphate).
c) lagoons
d) filtration
2. Persons working in cement plants and limestone quarries are more prone to disease like

a) cancer
b) asthma
c) silicosis
d) .flourosis (bone disease)
3. Particulates (< 1μm size) remaining suspended in air indefinitely and transported by wind currents
are called

a) fumes
b) mists
c) smoke
d) Aerosol
4. Operating principle of cyclone separator is based on the action of __________ dust particles.

a) diffusion of
b) centrifugal force on
c) gravitational force on
d) electrostatic force on
5. Exposure to small amount of __________ results in high blood pressure & heart disease in human
beings.

a) hydrogen sulphide
b) mercury
c) cadmium
d) asbestos
6. Maximum allowable concentration of CO2 in air for safe working is __________ ppm (parts per
million).

a) 50
b) 1000
c) 2000
d) 5000
7. 7.Tolerable limit of nitrogen oxides in air is __________ ppm.

a) 0.1
b) 1
c) 5
d) 25
8. During which of the following operating conditions of an automobile, carbon monoxide content in
the exhaust gas is maximum ?

a) Idle running
b) Acceleration
c) Cruising
d) Deaccelaration
9. H2S present in gaseous stream can be removed by adsorption on
a) silica gel
b) active carbon
c) bog iron
d) limestone powder

10. Threshold Limit Value (TLV) is the maximum allowable concentration (i.e. safe limit) of pollutants
in air. Safe limit for SO2 in air is __________ ppm.

a) 5
b) 500
c) 1000
d) 2000
11. Most of the atmospheric air pollutants are present in large quantity in

a) stratosphere
b) thermosphere
c) trophosphere
d) mesosphere
12. Pick out the wrong statement.

a) Caustic embrittlement of boiler's metallic parts is caused by high concentration of caustic

soda in boiler feed water.
b) Cooling and freezing of water kills the bacteria present in it.
c) With increasing boiler operating pressure of steam, the maximum allowable concentration
of silica in feed water goes on decreasing.
d) Dissolved oxygen content in high pressure boiler feed water should be nil.
13. 'Pneumoconiosis' is a disease caused by the inhalation of __________ dust.

a) coal
b) uranium ore
c) iron ore
d) lime

14. Most efficient and suitable dust removal equipment for removal of flyash from flue gas in a
thermal power plant is the

a) gravity settling chamber

b) cyclone separator
c) electrostatic precipitator
d) bag filter
15. Which of the following is not a secondary air pollutant ?
 a) Ozone
b) Photochemical smog
c) Sulphur dioxide
d) All (a), (b) & (c)
16. The concentration of water vapour in troposphere, which depends upon the altitude &
temperature varies in the range of zero to __________ percent.

a) 1
b) 4
c) 8
d) 12
17. The main industrial source of emission of hydrogen sulphide air pollutant is

a) petroleum refineries.
b) coal based thermal power plants.
c) pulp and paper plant.
d) metallurgical roasting & smelting plant.
18. Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about
__________ decibels.

a) 90
b) 120
c) 150
d) 180
19. Nitrogen oxides (NOx) is not produced in the __________ industry.

a) nitric acid making

b) nitrogenous fertiliser
c) detergent
d) any of these
20. World's worst radioactive pollution was caused by nuclear reactor disaster which occured in

a) Arizona (U.S.A.)
b) Chernobyl (undivided U.S.S.R.)
c) Pensylvania (U.S.A.)
d) Moscow (U.S.S.R.)
21. Dissolved oxygen content in river water is around __________ ppm.

a) 5
b) 100
c) 250
d) 500
22. Oil and grease present in an emulsified state in waste water discharged from industries can be
removed by

a) biological oxidation.
b) skimming off.
c) settling out using chemical reagents.
d) chlorination.
23. The amount of chemical coagulant added for treatment of polluted water __________ with
increase in temperature of the polluted water to be treated.

a) decreases.
b) increases.
c) remains constant.
d) may increase or decrease ; depends on the chemical characteristics of polluted water
24. Particles having diameter greater than 75 μm (micrometer = 10-6 mm) are called

a) grit
b) dust
c) powder
d) smoke
25. Presence of bacteria in potable (drinking) water causes

a) turbidity
b) disease
c) bad odour
d) bad taste & colour
26. What are the methods of treatment & disposal of radioactive wastes ?

a) Evaporation & chemical precipitation.

b) Biological methods & adsorption in ion exchange materials.
c) Fixing into a solid mass with cement and sinking deep in the sea.
d) All (a), (b) & (c).
27. Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it.
Presence of bacteria helps in

a) coagulation and flocculation of colloids.

b) oxidation of carbonaceous matter to CO2.
c) nitrification or oxidation of ammonia derived from breakdown of nitrogeneous organic
matter to the nitrite and eventually to the nitrate.
d) all (a), (b) and (c).
28. Peroxyacyl nitrate (PAN), a pollutant is found in the

a) automobile exhaust.
b) flue gas of coal based power plant.
c) exhaust of nitric acid plant.
d) exhaust of sulphuric acid plant.
29. Foaming and priming in boiler operation can be reduced by reduction in __________ in feed
water.

a) turbidity
b) color (Hazen)
c) total solids
d) all (a), (b) & (c)
30. Which of the following radioactive wastes emits all α, β & γ rays and hence is the most hazardous
of all radioactive emitters?

a) I-131
b) Sr-90
c) Au-198
d) Ra-226
31. Maximum permissible turbidity in potable water is __________ ppm.

a) 1
b) 10
c) 250
d) 1000
32. Presence of __________ hardness is responsible for the temporary hardness in water.

a) carbonate
b) calcium
c) choride
d) sulphate
33. Dose of chlorine for disinfection of water is about __________ mg/litre of water.

a) 0.01
b) 0.1
c) 0.3
d) 1
34. A shallow pond in which the sewage is retained and biologically treated is called

a) oxidation
b) Imhoff tank
c) lagoon
d) skimming tank
35. Which is the most practical and economical method for removal of suspended solid matter from
polluted water?

a) Sedimentation
b) Skimming off
c) Chlorination
d) Biological oxidation
36. Iron & manganese present in the polluted water is removed by

a) simple filtration.
b) oxidation followed by settling & filtration.
c) chemical coagulation.
d) chlorination only.
37. Water effluent generated in printing industry is decolourised by

a) ion exchange technique.

b) reverse osmosis.
c) electrolytic decomposition.
 d) adsorption.
38. Thermal pollution of water increases its toxicity and oxidation of oxygen demanding waste
besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of
__________ present in it.

a) coal ash
b) potassium cyanide
c) ortho-xylene
d) none of these
39. Ozone level is generally found to be depleted in India in the month of

a) February
b) July
c) April
d) December
40. Foul odour and bad taste of water is removed by treating with

a) alum
b) bleaching powder
c) activated carbon
d) copper sulphate.
41. Presence of __________ in water stream are deleterious to aquatic life.

a) soluble and toxic organics.

b) suspended solids.
c) heavy metals and cynides.
d) all (a), (b) & (c).
42. Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air
exceeds __________ percent (by volume).

a) 1
b) 3
c) 7
d) 20
43. Presence of soluble organics in polluted water causes

a) undesirable plants growth.

b) depletion of oxygen.
c) fire hazards.
d) explosion hazards.
44. Which of the following pollutants, if present in atmosphere is detectable by its odour ?

a) CO
b) SO2
c) NO2
d) CO2
45. Exposure to chemicals having carcinogenic properties cause

a) dermatitis (skin disorder)

 b) cancer
c) asphyxiation
d) asthma
46. In water treatment plant, zeolite process is used to remove the __________ of water.

a) acidity
b) alkalinity
c) hardness
d) iron & zinc
47. For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than
__________ ppm.

a) 10000
b) 5
c) 500
d) 1000
48. Fresh sewage is __________ in nature.

a) acidic
b) neutral
c) alkaline
d) highly acidic
49. Workers working in __________ industry are most prone to white lung cancer.

a) coal mining
b) limestone mining
c) textile
d) asbestos
50. A standard test for determination of hardness in water is termed as __________ test.

a) EDTA
b) electometric
c) total count
d) presumptive
51. TLV of lead for public sewer/waste water is about __________ ppm.

a) 1
b) 25
c) 150
d) 650
52. Presence of nitrates in water in excess of 50 ppm causes

a) mathenoglobenemia
b) gastroentetitis
c) asphyxiation
d) tooth decay
53. The lowest layer of atmosphere is known as the

a) stratosphere
 b) troposphere
c) ionosphere
d) none of these
54. As per the world health organisation (WHO) specification, the maximum permissible
concentration (i.e., TLV) of particulate matter in air is __________ μg/m3.(μg-microgram)

a) 10
b) 90
c) 800
d) 750
55. Which of the following is not a weightless pollutant ?

a) SPM
b) Thermal pollution
c) Radioactive rays
d) Noise pollution
56. Which of the following is the most lethal water pollutant ?

a) Phenol and cynide

b) Chlorine
c) Alkalis
d) Suspended solids
57. The permissible color for domestic water supply is __________ ppm.

a) 1
b) 20
c) 100
d) 1000
58. Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off by

a) quenching of hot coke.

b) discharging in the river stream.
c) filtration and recycling for cooling coke oven gas.
d) none of these.
59. Radioactive substances present in the polluted water stream can be removed by

a) biological oxygen treatment.

b) coagulation and filtration.
c) adsorption in ion exchange materials.
d) none of these.
60. Main pollutants released from petroleum refineries is

a) CO, SO2 & H2S.

b) CO2, NO & SO3.
c) CO2, H2S & NO2.
d) SO3, NO2 & CO2.
61. Carbon monoxide is a pollutant, which causes

a) respiratory disease (e.g. asthma).

 b) asphyxiation (suffocation) leading to death.
c) retardation in crop growth.
d) damage to building materials like marble.
62. Pollution by particulate matter emission in the atmosphere does not take place during metal

a) grinding
b) machining
c) cutting
d) polishing
63. Irradiation of water by ultraviolet light of suitable wavelength is commonly used for disinfection
of water in

a) food industry.
b) municipal sewage treatment.
c) petroleum refinery.
d) iron & steel plant.
64. Presence of a certain minimum quantity of fluorine is desirable in potable water to prevent

a) dental cavities
b) scale formation
c) water-borne disease
d) corrosion
65. Algae growth in water is controlled by

a) deoxidation
b) chlorination
c) bleaching
d) aeration
66. __________ is removed from water by lime-soda process.

a) Foul smell and taste

b) Iron and manganese
c) Temporary hardness
d) Permanent hardness
67. Thermal pollution due to excessive heat & temperature in the working place causes

a) reduction in working efficiency of manpower.

b) fatigue.
c) high breathing rate.
d) all (a), (b) & (c).
68. World environment day is observed every year on the 5th of

a) June
b) December
c) July
d) September
69. Infective bacteria in water is killed by the __________ process.

a) sterilisation
 b) aeration
c) disinfection
d) none of these
70. Fluorosis is caused due to the presence of excessive amount of __________ in drinking water.

a) mercury
b) lead
c) fluoride
d) arsenic
71. Presence of nitrogen and phosphorous in waste water discharged into lakes and ponds causes

a) foaming
b) odour nuisances
c) undesirable plant growth
d) turbidity
72. The pH value of potable water should be between

a) 1 to 1.5
b) 6.5 to 8
c) 13 to 14
d) 4 to 5
73. Maximum permissible limit of mercury in human blood is __________ micrograms/100 c.c.

a) 1
b) 7
c) 19
d) 82
74. Salt content in sea water is about __________ percent.

a) 0.5
b) B. 1
c) 3.5
d) 10
75. What is the major constituents of waste/polluted water discharged from textile, pulp & paper,
tanning, distillary, dairy and meat packing industries ?

a) Radioactive substances
b) Natural organic products
c) Inorganic pollutants
d) None of these
76. Disinfection of water is done to remove

a) color
b) bad taste
c) foul odour
d) bacteria
77. In large thermal power stations very fine particulates present in flue gas are removed by

a) wet scrubber
 b) bag filter
c) electrostatic precipitators
d) dust catcher
78. Inorganic impurities causing water pollution is

a) fats
b) carbohydrates
c) salts of metals
d) protein
79. From pollution control point of view, the maximum permissible concentration of sulphur dioxide
in atmospheric air is about __________ ppm.

a) 1
b) B. 5
c) 50
d) D. 500
80. Presence of __________ bacteria in water causes disease like typhoid.

a) aerobic
b) pathogenic
c) anaerobic
d) non-pathogenic
81. Reingleman chart is used for the evaluation of __________ pollution.
a) air
b) water
c) noise
d) radioactive
82. Hydrogen ion concentration in distilled water is
a) 10-7
b) 7 x 10-7
c) 107
d) 7 x 107
83. Which of the following is not a practical method of low level radioactive waste disposal ?

a) Dilution with inert material.

b) Discharging to atmosphere through tall stacks after dilution.
c) Disposing off in rivers & oceans.
d) Filling in steel crates and shooting it off out of earth's gravity.

84. Removal of __________ results from the disinfection of water.

a) turbidity
b) odour
c) hardness
d) bacteria
85. Radioactive solid nuclear wastes are disposed off by

a) high temperature incineration.

 b) pathological incineration.
c) pyrolysis.
d) underground burial in concrete containers.
86. Growth of __________ is promoted by the presence of manganese in water.

a) files
b) algae
c) micro-organisms
d) mosquitoes
87. Average human body contains about __________ percent water by weight.

a) 20
b) 40
c) 70
d) 85

UNIT 2
01. Air pollution may be caused by :

a) human activities
b) natural disastrous events
c) both (a) and (b)
d) none of the above

02. Air pollution causes harmful effects on:

a) biotic activities
b) abiotic world
c) both (a) and (b)
d) none of the above

03. The average consumption of air by an adult human being is of the order of:

a) 5 kg
b) 12 kg
c) 25 kg
d) none of them

04. ‘London smog’ was primarily caused by:

a) burning of coal
b) burning of oil
c) eruption of a volcano
d) none of the above

05. Which of the following is not an anthropogenic cause of air pollution?

a) Burning of fossil fuels

 b) Burning of firewood
c) Agricultural activities
d) Burning of forests due to lighting.

06. The factor which is primarily responsible for causing air pollution in modern days is:

a) Industries and automobiles

b) Dust storms
c) Forest fires
d) None of them

07. About 90% of world’s air pollution is caused by:

a) Primary air pollutants

b) Secondary air pollutants
c) Volcanism
d) None of them

08. The primary air pollutant which is formed due to incomplete combustion of organic matter is:

a) Methane
b) Sulphur dioxide
c) Ozone
d) Carbon monoxide

09. Among the following, the only secondary pollutant is:

a) Sulphur dioxide
b) Hydrocarbons
c) Ozone
d) Sulphur tetraoxide

10. Which of the following is not a secondary air pollutant:

a) Sulphuric acid
b) Formaldehyde
c) Peroxyacyl nitrate
d) None of the above

11. Hairs of human nose can remove all particles of size greater than:

a) 1 mm
b) 1 micron
c) 10 micron
d) 100 micron

12. The chemical compounds which are responsible for production of photochemical smog are:

a) Hydrocarbons
b) Oxides of nitrogen
c) both (a) and (b)
d) none of them
13. The poisonous gas responsible for causing the catastrophic Bhopal gas tragedy in 1984 in India
was:

a) sulphur dioxide
b) methyl isocyanate
c) carbon dioxide and methane both
d) laughing gas

14. Which of the following is not a major constituent of a photochemical smog?

a) PAN
b) CO
c) HC
d) O3

15. The major photochemical oxidant is:

a) Hydrogen peroxide
b) Ozone
c) Nitrogen oxides
d) PAN

16. The particles in cigarette smoke are usually smaller than:

a) 1 micron
b) 10 micron
c) 25 micron
d) 100 micron

17. The most hazardous gaseous air pollutant for human health is:

a) Carbon dioxide
b) Oxygen
c) Nitrogen
d) Sulphur dioxide

18. During temperature inversion in atmosphere, air pollutants tend to:

a) Accumulate above inversion layer

b) Accumulate below inversion layer
c) Disperse laterally
d) Disperse vertically

19. Electrostatic precipitators remove:

a) SO2
b) Particulate matter
c) both (a) and (b)
d) none of them

20. The percentage of particles eminating from cigarette smoking, which get deposited in lungs, is
about:

a) 10%
 b) 25%
c) 65%
d) 100%

21. The Respiratory Suspended Particulate Matter (RSPM) concentration includes all particles in air
mass of size up to:

a) 10µ
b) 25µ
c) 50µ
d) None of them

22. The RSPM is also designated as:

a) PM 2.5
b) PM 10
c) PM 25
d) None of them

23. The air pollutant which causes sever damage to plants, even at much lower concentration than
what may be harmful to human health, is:

a) Fluorine
b) Ozone
c) PAN
d) Nine of them

24. The air pollutant which does not cause any major adverse impacte on the cattle is:

a) Fluorine
b) Arsenic
c) Lead
d) None of them

25. According to EPA of USA, the following is not one of the six major pollutants?

a) Ozone
b) Carbon monoxide
c) Nitrogen oxides
d) Carbon dioxide

26. The Pollution Standard Index (PSI) scale has span from

a) 0-200
b) 0-300
c) 0-400
d) 0-500

27. Which of the following is an organic gas?

a) Hydrocarbons
b) Aldehydes
c) Ketones
 d) Ammonia

28. The major contributor of Carbon monoxide is

a) Motor vehicle
b) Industrial processes
c) Stationary fuel combustion
d) None of the above

29. Ozone of found in

a) Mesosphere
b) Ionosphere
c) Stratosphere
d) Exosphere

30. Ozone is formed in the upper atmosphere by a photochemical reaction with

a) Ultra violet solar radiation

a) Infra red radiation
b) Visible light
c) All of the above

31. The threshold concentration of sulphur dioxide in any industrial activity should not be permitted
beyond

a) 2ppm
b) 3ppm
c) 4ppm
d) 5ppm

32. The max. permissible average annul standard for NO2 for residential, industrial and other areas
under the new revised NAAQS in India is:

a) 30 µg/m3
b) 40 µg/m3
c) 60 µg/m3
d) 120 µg/m3

33. Sulphur dioxide exposures to quantities higher than permissible in ambient air may cause:

a) Breathing and respiratory illnesses

b) Hay fever
c) Typhoid
d) Malaria

34. High lead exposures in humans through inhalations or food may cause:

a) Mental retardation
b) Disorder of central nervous system
c) High blood pressure
d) All of the above
35. Higher exposures of humans to nitrogen oxides may cause:

a) Bronchitis
b) pneumonia
c) Allergies and viral attacks
d) All of the above

36. Carbon monoxide is hazardous to health, because:

a) It causes loss of sense of smell

b) It is carcinogenic in nature
c) It reduces oxygen carrying capacity of blood
d) It may cause conjunctivitis

37. Longer exposure to NO2 even in small concentrations may cause diseases pertaining to:

a) Lever
b) Lung
c) Kidneys
d) Heart

38. Heavy loading of pollen grains in air may cause:

a) Anaemia
b) Typhoid
c) Hayfever
d) Influenza

39. The permissible annual average standard of PM10 (RSPM) ambient air quality standard for
standard residential areas in India is:

a) 60 µg/m3
b) 80 µg/m3
c) 90 µg/m3
d) 100 µg/m3

40. The most significant primary gaseous pollutant, found in vehicular emissions, is:

a) CO
b) CO2
c) SO2
d) O3

41. The device, which can be used to control gaseous as well as particulate pollutants in the
industrial emissions, is known as:

a) Cyclone
b) Spray tower
c) Dynamic precipitator
a) Fabric filter

42. According to the WHO’s reports of 1992, the most polluted city in the world, is;
 b) Delhi
c) Bangkok
d) Newyork
e) Tokyo

43. The polluting gas, which is primarily responsible for causing the green house effect and global
warning, is:

a) Sulphur dioxide
b) Hydrogen sulphide
c) CO2
d) Noine of them

44. The zone on Earth, where alone life exists, is called:

a) Hydrosphere
b) Lithosphere
c) Biosphere
d) Troposphere

45. The world ozone day is celebrated on:

a) 16th sep
b) 31st Dec
c) 14th Jan
d) 22nd june

46. The possible substitutes of CFCs are:

a) HCFs
b) ODSs
c) Halons
d) All of the above

47. How much CO2 can a tree remove annually from the air?

a) 1 kg
b) 5 kg
c) 15 kg
d) 50 kg

48. The CO2 in Earth’s atmosphere, has during the last about 50 years, increased by about:

a) 1%
b) 5%
c) 10%
d) 20%

49. Which of the following is an air pollutant?

a) Nitrogen
b) Carbon dioxide
c) Carbon monooxide
 d) Oxygen

50. Which of the following is a secondary air pollutant?

a) Ozone
b) Carbon dioxide
c) Carbon monooxide
d) Sulphur dioxide

51. The environmental lapse rate is found to be:

a) 6.5°C/km
b) 8.6°C/km
c) 6.5°C/km
d) 5.6°C/km

52. During Inversion:

a) Temperature increases with altitude

b) Temperature decreases with altitude
c) Temperature remains constant
d) None of the above

53. Among the following, the only secondary pollutant is:

a) Sulphur tetraoxide
a) Sulphur dioxide
b) Ozone
c) Sulphur tetraoxide

54. Which of the following groups of plants can be used as indicators of SO pollution of air?

a) Epiphytic lichens
b) Ferns
c) Liver worts
d) Horn worts

55. Which of the following on inhalation dissolved in the blood hemoglobin more rapidly than
oxygen?

a) Sulphur dioxide
b) Carbon mono-oxide
c) Ozone
d) Nitrous oxide

56. Smog is:

a) A natural phenomenon
b) A combination of smoke and fog
c) Is colourless
d) All of the above
57. The major photochemical oxidant is:

a) Ozone
b) Hydrogen peroxide
c) Nitrogen oxides
d) Peroxyl Acetyl Nitrate (PAN)

58. Which of the following are likely to be present in photochemical smog?

a) Sulphur dioxide
b) Photochemical oxidants
c) Chlorofluorocarbon
d) Smog

59. Which of the following devices is suitable for the removal of gaseous pollutants?
a) Cyclone separator
b) Electrostatic precipitator
c) Fabric filter
d) Wet scrubber

60. Which of the following air pollution control devices is suitable for the removing the finest dust
from the air?
a) Cyclone separator
b) Electrostatic precipitator
c) Fabric filter
d) Wet scrubber

61. Air pollution from automobiles can be controlled by fitting:

a) Cyclone separato
b) Electrostatic precipitator
c) Catalytic converter
d) Wet scrubber

62. Taj Mahal at Agra may be damaged by:

a) Sulphur dioxide
b) Chlorine
c) Hydrogen
d) Oxygen

63. Gas leaked in Bhopal tragedy:

a) Methyl isocyanate
b) Potassium isothoiocynate
c) Ethyl isocyanate
d) Sodium isothiocyanate

64. BOD is:

a) A measure of the organic matter presents in water
b) Usually less than COD
c) Biochemical oxygen demand
d) All of the above

65. BOD/COD ratio will always be:

 a) Equal to 1
b) Less than 1
c) More than 1
d) None of them

66. Biochemical Oxygen Demand measures:

a) Industrial pollution
b) Air pollution
c) Pollution capacity of effects
d) Dissolved O2 needed by microbes to decompose organic waste

67. What is the harm from the depletion of Earth's ozone layer

a) The average temperature of earth's surface will increase gradually

b) The oxygen content of the atmosphere will decrease
c) Increased amount of Ultra violet radiation will reach earth's surface
d) Sea levels will rise as the polar ice caps will gradually melt

68. Acid rain is formed due to contribution from the following pair of gases

a) Methane and ozone

b) Oxygen and nitrous oxide
c) methane and sulpher dioxide
d) Carbon dioxide and sulpher dioxide

69. Which of the following is a prime health risks associated with greater UV radiation through the
atmosphere due to depletion of stratospheric ozone?

a) Damage to digestive system

b) Increased liver cancer
c) Neurological disorder
d) Increased skin cancer
70. The most serious environmental effect posed by hazardous wastes is

a) air pollution.
b) contamination of groundwater.
c) increased use of land for landfills.
d) destruction of habitat.
e) none of the above.

71. The concentration of which gas is highest in our environment?

a) Oxygen
b) Hydrogen
c) Nitrogen
d) Carbon dioxide

72. Which of the following is not as a consequence of global warming?

a) rising sea level

b) increased agricultural productivity worldwide
c) worsening health effects
 d) increased storm frequency and intensity
e) all of the above are likely results of global warming

73. Which of the following is not a primary contributor to the greenhouse effect?

a) carbon dioxide
b) carbon monoxide
c) chlorofluorocarbons
d) methane gas
e) nitrous oxide

74. The increase in the concentration of CO2 in our environment in last fifty years; since 1960 is
about

a) 20%
b) 10%
c) 14%
d) 6%

75. The depletion in the Ozone layer is caused by

a) nitrous oxide.
b) carbon dioxide.
c) chlorofluorocarbons.
d) methane.
e) all of the above.

76. A major in-stream use of water is for

a) producing hydroelectric power.

b) dissolving industrial wastes.
c) agricultural irrigation.
d) domestic use.
e) none of the above.

UNIT-III

1. Thermal pollution of water increases its toxicity and oxidation of oxygen demanding waste besides
favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of
__________ present in it.

a) coal ash
b) potassium cyanide
c) ortho-xylene
d) none of these

2. __________ can not control the noise pollution.

a) Use of silencers
b) Green house gases
 c) Vibration damping
d) Tree plantation

3. Ozone level is generally found to be depleted in India in the month of

a) February
b) July
c) April
d) December

4. Noise level during normal conversation among men is about __________ decibels.

a) 10
b) 45
c) 90
d) 115

5. 'Particulate' air pollutants are finely divided solids and liquids. Which of the following is not a
‘particulate’?

a) Dust & mists

b) Smoke & fumes
c) Photochemical smog & soot
d) None of these

6. Foul odour and bad taste of water is removed by treating with

a) alum
b) bleaching powder
c) activated carbon
d) copper sulphate

7. Presence of __________ in water stream is deleterious to aquatic life.

a) Soluble and toxic organics.

b) Suspended solids.
c) heavy metals and cyanides
d) Above all

8. Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air
exceeds __________ percent (by volume).

a) 1
b) 3
c) 7
d) 20

9. Methyl iso-cynate (MIC) gas (TLV <1 ppm), which caused Bhopal gas tragedy in 1984 falls under
the category of __________ toxic gas.

a) moderately
b) highly
 c) extremely
d) very extremely

10. Noise level heard inside a bus in busy city traffic or inside a sub-way train corresponds to about
__________ decibels.

a) 75
b) 95
c) 120
d) 140

11. Presence of volatile compounds like gasoline, oil, alcohol, ether etc. in municipal sewers may
cause

a) explosion
b) non-biodegradable foam
c) undesirable plant growth
d) corrosion

12. Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is
mainly caused due to the turbulence created by blade passage through air. It can be reduced by use
of a slower fan

a) With greater number of blades

b) Of increased diameter
c) Both (a) & (b)
d) Neither (a) nor (b)

13. Presence of soluble organics in polluted water causes

a) Undesirable plants growth.

b) Depletion of oxygen.
c) Fire hazards.
d) Explosion hazards.

14. Which of the following pollutants, if present in atmosphere is detectable by its odour ?

a) CO
b) SO2
c) NO2
d) CO2

15. Exposure to chemicals having carcinogenic properties cause

a) dermatitis (skin disorder)

b) cancer
c) asphyxiation
d) asthma

16. Ambient noise level can be reduced by __________ decibels by planting trees (like coconut,
neem etc.) near public utility buildings (like hospitals & schools).
 a) 1-2
b) 5-10
c) 15-20
d) 25-30

17. Pick out the wrong statement.

a) Catalytic converter is fitted in automobiles to reduce carbon monoxide concentration in

exhaust emissions.
b) Inhalation of pollutant carbon monoxide results in death by asphyxiation.
c) Sulphur dioxide is the main pollutant emitted from the exhaust of petrol driven automobiles.
d) Decomposition of plants containing chlorophyll is a natural source of carbon monoxide in
atmosphere.

18. Noise level heard at a distance of about 100 metres from a jet engine with after burner is about
__________ decibels.

a) 120
b) 140
c) 170
d) 200
19. TLV of mercury in potable (drinking) water is about __________ ppm.

a) 0.001
b) 0.1
c) 1
d) 5

20. Which is the best and the most effective method for the removal of organic contaminant
present in the polluted water in very small quantity (say < 200 mg/litre)?

a) Lagooning
b) Activated carbon adsorption
c) Biological oxidation pond
d) Chemical coagulation

21. Which is a secondary air pollutant ?

a) Photochemical smog
b) Sulphur dioxide
c) Nitrogen dioxide
d) Dust particles

22. Siderosis is a disease caused by the inhalation of __________ dust.

a) coal
b) silica
c) iron
d) none of these
23. Noise level audible to audience sitting in the 5th row from the stage during a large orchestra
show corresponds to about __________ decibels.

a) 105
b) 135
c) 160
d) 185

24. If carbon monoxide content in atmospheric air exceeds __________ ppm, death is bound to
occur.

a) 50
b) 500
c) 1000
d) 3000

25. Coal mines drainage waste water (acidic in nature) results from the earth's water percolating
through the voids created in coal bed during mining. This polluted water which either drains out
naturally to water courses or are removed before starting the mining is

a) neutralised by alkali treatment.

b) left as such without any treatment.
c) diluted with fresh water to reduce its acidity.
d) none of these.

26. Fine grit present in sewage is removed in the __________ during sewage treatment.

a) grit chamber
b) detritus tank
c) trickling filter
d) skimming tank

27. The lowest layer of atmosphere is known as the

a) stratosphere
b) troposphere
c) ionosphere
d) none of these

28. As per the world health organisation (WHO) specification, the maximum permissible
concentration (i.e., TLV) of particulate matter in air is __________ μg/m3.(μg-microgram)

a) 10
b) 90
c) 800
d) 750

29. Which of the following is not a weightless pollutant ?

a) SPM
b) Thermal pollution
c) Radioactive rays
 d) Noise pollution

30. Global warming may result in

a) flood
b) cyclone
c) decrease in food productivity
d) all (a), (b) and (c)

31. Which of the following is the most lethal water pollutant?

a) Phenol and cyanide

b) Chlorine
c) Alkalis
d) Suspended solids

32. Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyll and

haemoglobin breakdown of some animals, beyond TLV (>50 ppm)

a) Acts as a greenhouse gas thereby raising earth's temperature.

b) Causes asphyxia.
c) Causes increase in sea level.
d) Enhances the greenhouse effect.

33. The earth's atmosphere is an envelope of gases present up to a height of about __________ km

a) 10
b) 200
c) 1000
d) 2000

34. Which of the following is an adsorbent used for the removal of SO2 from gas/air ?

a) Bog iron
b) Limestone powder or alkalised alumina
c) Silica gel
d) Active carbon

35. Higher concentration of nitrogen dioxide in atmospheric air causes

a) cancer
b) bronchitis
c) asphyxiation
d) corrosion

36. Ozone is

a) a primary pollutant
b) a secondary pollutant.
c) impervious to ultra-violet rays.
d) both (b) and (c)

37. The permissible color for domestic water supply is __________ ppm.
 a) 1
b) 20
c) 100
d) 1000

38. High noise levels produced during operation of fans and compressors can be reduced by using

a) mufflers (silencers).
b) accoustical absorbent.
c) lagging of noisy duct.
d) none of these.

39. The Killer gas which caused Bhopal gas tragedy in 1984 was

a) phosgene
b) methyl iso-cynate (MIC)
c) carbon monoxide
d) sulphur dioxide

40. Aerosols present in atmospheric air may be

a) positively charged.
b) negatively charged.
c) neutral.
d) combination of all (a), (b) & (c).

41. Ethanolamine is an absorbant used for the removal of __________ from air/gas.

a) HF
b) SO2
c) H2S
d) both (b) & (c)

42. Which of the following causes death by asphyxiation, if its presence in atmospheric air exceeds
maximum allowable concentration (i.e. > 50 ppm) ?

a) Benzopyrene
b) Peroxyacyl nitrate
c) Carbon monoxide
d) Sulphur dioxide

43. __________ plant emits large amount of SO2 as an air pollutant.

a) Nitric acid
b) Sulphuric acid
c) Chloralkali
d) Iron & steel

44. Noise pollution level in a chemical plant is expressed in

a) roentgen
b) decibel
c) hertz
 d) none of these

45. The maximum permissible noise level to which a man working in a chemical plant can be
exposed for eight hours per day is about __________ decibels.

a) 60
b) 90
c) 105
d) 120

46. The most commonly used chemical coagulant in water treatment is

a) ferrous sulphate
b) alum
c) lime
d) hydrazine

47. The biological decomposition of organic substances in wastes controlled conditions is called

a) incineration
b) biological oxidation
c) composting
d) none of these

48. Lung cancer & DNA breakage are the major ill effects of excessive ozone exposure to human
beings. Ozone layer depletion in the atmosphere is mainly caused by the presence of

a) CO2
b) SO2
c) hydrocarbons
d) CFC (chloro fluoro carbon)

49. Smog is not formed due to the presence of __________ in the atmosphere.

a) SO2
b) NOx
c) CO2
d) any of these

50. Pick out the correct statement.

a) Deforestation helps in controlling the green house effect.

b) Global warming is detrimental for increase in food productivity and may cause flood and
cyclone
c) Lightening discharges are natural source of production of SO2 & H2S pollutant.
d) Sulhur dioxide causes death by asphyxiation.

51. Which of the following is not a source of ozone emission in the atmosphere ?

a) Refrigerators.
b) Xerox machines.
c) Dermatological photo-therapy equipments.
 d) High voltage electrical equipments.

52. Oceans act as sinks for atmospheric gases including carbon dioxide whose concentration in the
atmosphere is increased by the

a) forestation
b) rain
c) green house effect
d) vegetation

53. Pick out the correct statement.

a) Chemical oxygen demand (COD) is a measure of chemically oxidisable organic matter

present in water.
b) COD is determined by oxidising the organic matter present in water with potassium
dichromate in cone, sulphuric acid solution at boiling temperature for specified time.
c) COD is related to BOD of a given waste in water but the relationship varies for different
wastes. Typically COD of potable water may be 1-2 mg/litre.
d) all (a), (b) and (c).

54. The upper layer of atmosphere is called the

a) stratosphere
b) troposphere
c) ionosphere
d) none of these

55. 5-200 μm size particles are called

a) colloids or aerosols
b) powder
c) dust
d) smoke

56. The effect of increase in carbon dioxide level of the atmosphere and its profound effect on our
climate is called the

a) catalytic conversion
b) green house effect
c) global warming
d) both (b) and (c)

57. Arsenic pollutant is not generated in____industries.

a) tanneries
b) glass & ceramic
c) beverages
d) any of these.

58. The resistance of water to the passage of light through it is a measure of the

a) turbidity
 b) color
c) hardness
d) dissolved gases

59. Color test of water is done with an instrument called

a) tintometer
b) colorimeter
c) electro-chemical cell
d) turbidimeter

60. Which of the following gases is having the widest explosion limit (about 2 to 81% gas in gas-air
mixture), rendering it the property of the most explosive gas ?

a) Hydrogen
b) Acetylene
c) Carbon monoxide
d) Ammonia

61. Smog is

a) nothing but black smoke.

b) a combination of smoke and fog.
c) a liquid particle resulting from vapor condensation.
d) a solid particle e.g. fly ash

62. __________ is the process of killing organism in water.

a) Coagulation
b) Sterilisation
c) Disinfection
d) Sedimentation

63. Reingleman chart No. 2 corresponds to __________ percent black smoke.

a) 10
b) 20
c) 40
d) 80

64. Which of the following is a manmade source of air pollution ?

a) Automobile exhaust.
b) Forest fire.
c) Bacterial action in soil and swamp areas
d) All (a), (b) and (c).

65. Which is the most efficient dust removal equipment for removal of sub-micronic dust particles
from blast furnace gas ?

a) Packed scrubber
b) Gravity settling chamber
 c) Electrostatic precipitator
d) Hydrocyclone
66. Beyond what concentration of H2S in air, acute danger to human life exists ?

a) 50 ppm
b) 100 ppm
c) 300 ppm
d) 700 ppm

67. Reingleman chart is used for the evaluation of __________ pollution.

a) air
b) water
c) noise
d) radioactive

68. There are five concentric layers within the atmosphere which is differentiated on the basis of
temperature. The atmospheric layer which lies close to the earth's surface in which human being
along with other organisms live is called troposphere. The rate at which air temperature in the
troposphere gradually decreases with height is about __________ °C/km.

a) 0.05
b) 1
c) 6.5
d) 15

69. Brown spots in fabrics will be caused by washing with water containing large amount of .

a) iron
b) zinc
c) iodine
d) bromine

70. Maximum permissible concentration (i.e. TLV) of DDT in public water supply system is
__________ micro gram (μ g)/litre.

a) 2
b) 42
c) 332
d) 1050

UNIT 4

1. The world as World Environmental day is celebrated on:

a) December 1
b) June 5
c) November 14
 d) August 15

2. The provisions for environmental protection in the constitution were made in:

a) 1976
b) 1950
c) 1982
d) 1960

3. The provisions of environmental protection in the constitution were made under:

a) Article 5-A
b) Article 21-B
c) Article 27-B (h)
d) Article 48-A and Article 51-A (g)

4. The first of the major environmental protection act to be promulgated in India was:

a) Water Act
b) Air Act
c) Environmental Act
d) Noise Pollution Rule

5. The Forest (Conservation) Act was enacted in the year:

a) 1986
b) 1974
c) 1980
d) 1972

6. The Forest (Conservation) Act extends to the whole of India except:

a) Uttar Pradesh
b) Karnataka
c) Jammu and Kashmir
d) Haryana

7. Penalty for conservation of the provisions of the Forest Act is under:

a) Section 3A
b) Section 4A
c) Section 12A
d) Section 8A
8. Offences by the Authorities and Government Department in Forest Act is under:

a) Section 5B
b) Section 5A
c) Section 3B
d) Section 8A

9. The Wildlife (Protection) Act was enacted in the year:

a) 1986
b) 1974
c) 1994
d) 1972

10. The power to declare an area as a sanctuary or national park of central Government is Wildlife
(Protection) Act is under:

a) Section 38
b) Section 39
c) Section 18
d) Section 27

11. The Wildlife (Protection) Act contains:

a) 7 Chapters
b) 6 Chapters
c) 5 Chapters
d) 8 Chapters

12. The Wildlife (Protection) Act contains:

a) 66 Sections
b) 6 Sections
c) 7 Sections
d) 46 Sections

13. The Water (Prevention and Control of Pollution) Act was enacted in the year:

a) 1986
b) 1974
c) 1994
d) 1975
14. The Water Act contains:

a) 4 Chapters
b) 5 Chapters

c) 7 Chapters

d) 8 Chapters

15. The Water Act have:

a) 64 Sections
b) 68 Sections
c) 45 Sections
d) 62 Sections

16. The functions of Central Board are given under:

a) Section 16
b) Section 19
c) Section 25
d) Section 24

17. The functions of State Board are given under:

a) Section 16

b) Section 17

c) Section 21

d) Section 45

18. Power to give directions are declared under:

a) Section 16
b) Section 17
c) Section 18
d) Section 25

19. In the Water Act the entire National Capital Territory of Delhi has been declared as water
pollution prevention control area under:

a) Section 21
b) Section 23
c) Section 19
 d) Section 24

20. The Air (Prevention and Control of Pollution) Act was enacted in the year:

a) 1981
b) 1996
c) 2000
d) 1974

21. The Air Act contains:

a) 5 Chapters
b) 6 Chapters
c) 7 Chapters
d) 8 Chapters

22. The Air Act have

a) 56 Section
b) 54 Section
c) 58 Section
d) 62 Section

23. Noise pollution has been inserted as pollution in the Air Act in:

a) 1981
b) 1987
c) 1982
d) 2000

24. The Environmental (Protection) Act was enacted in the year:

a) 1986
b) 1992
c) 1984
d) 1974

25. The EPA consists:

a) 2 Chapters
b) 4 Chapters
c) 8 Chapters
d) 7 Chapters
26. The EPA contains:

a) 25 Sections
b) 12 Sections
c) 26 Sections
d) 14 Sections

27. NGO stands for:

a) Non-Governmental Organization
b) Nine-Governmental Organization
c) Non-Gained Organizations
d) National-Grade Organization

28. The Women’s Population in the world is almost:

a) Half
b) One-forth
c) One-third
d) One fifth

29. Literate women can help in:

a) Reducing infant mortality rate

b) Reducing population growth
c) Promoting female children education
d) All of the above

30. When was the water (prevention and control of pollution) act enacted by the Indian parliament?

a) 1970
b) 1974
c) 1980
d) 1985

31. One of the following factors does the population growth in a town normally depends?

a) Birth and Death rates

b) Migrations
c) Probabilistic growth
d) Logistic growth

Select the correct answer using the codes given below:

a) a and d
b) a and b
c) a, b and c
 d) b and c
32. Which of the following Acts/Rules has a provision for “No right to appeal”?

a) Environment (protection) Act, 1986

b) The Hazardous Waste (management and handling) Rules, 1989
c) Manufacturer, storage and impart of Hazardous chemical Rules, 1989
d) Environment (protection) rules, 1992

33. Which among the following brings about the Hazardous Waste Management and Handling Rule
in India?

a) Central pollution control board

b) Ministry of Environment and Forest
c) Ministry of Urban Development
d) Ministry of Rural Development

34. An important water contaminant is

a) Heavy metals
b) Nitrogen oxides
c) Carbon monoxide
d) NO2 and SO2

35. Which of the following pair is incorrectly matched w.r. to the air quality standard in industrial
and mixed use?

a) CO -->5000 µ/m2
b) SO2 --> 120 µ/m2
c) NOx --> 80 µ/m2
d) None of the above
36. The projects of which of the following are being assessed for Environmental Impact?

a) Irrigation and Power

b) Administration
c) Public investment
d) All of these
37. Parameter Importance Unit is:

a) a subjective process
b) a weight age given to parameters
c) a technique to select parameters
d) None of the above
38. Which is not an objective of EIA?

a) Recycling and reduction of waste

b) Risk analysis and disaster management
c) Assessment of international funding
d) All of the above
39. The average occupancy per passenger vehicle in India is:

a) 2
 b) 1.2
c) 2.5
d) 5
40. The important sector/s that feed the mankind is/are:

a) agriculture sector
b) forest and wildlife
c) livestock and fisheries
d) All of these
41. Environmental auditing helps in pollution control, improves production, safety and health and
conservation of natural resources by way of:

a) ensuring waste prevention and reduction

b) assessing compliance with regulatory environment
c) placing environmental information to the public
d) All of the above
42. Which is not correctly matched?

a) ISO International Organisation of Standards

b) EMS -> Environmental Management System
c) EIA -> Environmental Impact Assessment
d) WTO -> Whole Trade Output
43. The agency which is not certifying the ISO is:

a) Bureau of Indian Standards (BIS), Delhi

b) Quality Assurance Services (QAS)
c) Central Pollution Control Board (CPCB), Delhi
d) All Indian Inset of Local Self Government, Mumbai

44. Which of the following is an impact of SPM and RPM?

a) obscures vision
b) causes cancer
c) corrodes metals
d) initiates soil pollution

45. Population of India is growing at the rate of:

a) 1.23% per year

b) 2.12% per year
c) 3% per year
d) 5% per year

46. The false statement regarding the environmental impact assessment is:

a) Schedule I -> Lists of projects

b) Schedule II -> Application forms
c) Schedule III -> Details of EAC
d) All of the above

47. The important step/s in the predication of impacts is/are:

 a) Carrying out the evaluation of impacts
b) Study of EIA
c) Preparation of environmental management plan
d) All of the above

48. All the cases of diversion of forests land should be approved by:

a) Central Government
b) Conservator of Forests
c) State Land Use Board
d) Ministry of Environment and Forests

49. Land degradation is great challenge for India because of:

a) the 83 mha forest land, over half is used to various degrees

b) only 250 mha land of 330 mha possess any potential for production
c) 406 million of livestock have to supported on 13 mha land
d) All of the above

50. The approximate population of Urban India is:

a) 5.5 million
b) 25.7% of total population
c) 32% of total population
d) 1.5 billion

51. The environmental planning is:

a) The analysis of how we can prevent the poaching of environment

b) the analysis of how people impact natural resources
c) the analysis of how we can preserve our biodiversity
d) the supply of management tool to conserve our environment
52. The correct pair regarding the air quality monitoring technique is:

a) O2 -> Ultraviolet Photometry

b) SO2 -> Diffusion Tube
c) NO2 -> Infrared absorption
d) C, N, P -> Polyurethrane filter
53. An environmental audit helps in achieving the:

a) resource optimisation
b) waste minimization
c) public awareness
d) All of these
54. Ministry of Environment and Forests amended the Environmental Impact Assessment
notification public hearing mandatory for environmental clearance on:

a) April 10; 1997

b) Jan. 27; 1996
c) Jan. 27; 1997
d) April 03; 1998
55. The impacts caused by construction of dams and reservoirs include:

a) soil erosion
b) loss of vegetation cover
c) changes in microclimate
d) All of the above
56. All major project plans should be examined to ensure:

a) quality of environment
b) public health and safety
c) both of these
d) None of these
57. The areas up to the 100 meters around the premises such as hospitals, educational institutions
and courts are:

a) Silence Zones
b) Atrophic Zones
c) EMP Zones
d) Irrigation Zones
58. The agency that has laid down the standards for the control of pollution of air, water and noise
is:

a) Central Pollution Control Tribunal

b) Central pollution Control Agency
c) Ministry of Home Affairs
d) Central Pollution Control Board
59. The Government of India approved the EIA clearance on:

a) Jan. 26; 1996

b) April 03; 1998
c) Jan. 27; 1994
d) March 31; 1998

60. The comprehensive legislation that is truly a milestone in the field of environmental protection
was enacted in:

a) 1985
b) 1987
c) 1991
d) 1994

61. The legislation that provides a legal framework for the improvement of environment is:

a) Water (Prevention and Control of Pollution Act), 1986

b) Water (Prevention and Control of Pollution Act), 1989
c) Water Crisis and Pollution Act, 1994
d) Legislation yet to be declared

62. The environmental impact assessment of development projects has so far been done on the
basis of:
 a) the provisions of the Environment Protection Act, 1986
b) the provisions of the Municipalities Act, 1986
c) executive order of the President
d) All of the above

63. Organisms inhabiting a common environment belong to the same:

a) Species
b) Genus
c) Population
d) Community

64. A biotic community is an assemblage of:

a) food web
b) food chain
c) closely related species
d) interacting populations

65. A community is not able to survive without:

a) predator
b) non-living components
c) parasites
d) decomposers

66. Which of the following term is used for the "study of plant community"?

a) Phytology
b) Ecosystem
c) Phytosociology
d) Population ecology

67. A community that starts the process of succession in a habitat is called:

a) pioneer community
b) biotic community
c) abiotic community
d) artificial community

68. When the vegetation of any region reaches climatic climax, it is:

a) Hydrophytic
b) Xerophytic
c) Lithophytic
d) Mesophytic

69. Primary succession starts with:

a) Lichens
b) Trees
c) Herbs
d) Animals
70. In a biotic community, the most important for survival of animals is:

a) green food
b) day length
c) predator
d) soil moisture

71. The basic unit in ecological studies is population. The sum of all the populations of the same kind
of organism form:

a) Community
b) Species
c) Colony
d) Genus

72. Primary succession refers to the development of communities on a:

a) newly exposed habitat with no record of earlier vegetation

b) pond freshly filled with water after a dry phase
c) forest clearing after devastating fire
d) freshly cleared crop field

73. The first plants to appear on badly burnt forest area will most probably be:

a) Mosses
b) Liverworts
c) Ferns
d) Grasses

74. The quills of porcupine are an example of:

a) avoiding predation by defence

b) avoiding predation by escape
c) a chemical deterrent to escape
d) Mimicry

75. An advantage of being a herbivore that feeds only on one or a few related plant species is:

a) only a few detoxifying enzymes are needed

b) it is easy to obtain a well-rounded diet
c) it is easy to find enough food
d) there will be no other herbivore competing for the food source

76. A leaf adapted to a warm dry climate is:

a) large and thin

b) small and thin
c) large and thick
d) small and thick

77. An insect survives the cold of winter in a dormant stage by converting its glycogen to:

a) ATP
b) Alcohol
 c) Lactic acid
d) Brown fat

78. A community with no living green plant is:

a) rocky shore
b) plankton
c) a mud flat
d) the deep ocean floor

79. It is a flock of sheep what is it of lions?

a) Troop
b) Flock
c) Flight
d) Herd

80. In which type of community, the number of species per unit area will be more:

a) Temperate forest
b) Deciduous forest
c) Tropical rain forest
d) Taiga forest

81. Biotic potential is counteracted by:

a) limited food supply

b) predation G competition
c) All of the above