Which one of the following is a wrong statement? 

1. Most of the forests have been lost in tropical areas.
2. Ozone in upper part of atmosphere is harmful to animals.
3.Greenhouse effect is a natural phenomenon.
4. Eutrophication is a natural phenomenon in freshwater bodies.

Good ozone is found in the 

1. mesosphere

2.troposphere

3. stratosphere

4. ionosphere

Which country has the greatest contribution for the hole formation in ozone layer?

1. Russia

2. Japan

3. USA

4. Germany

The ‘thickness’ of Stratospheric Ozone layer is measured in/on:
1. Sieverts units
2. Dobson units
3. Melson units
4. Beaufort Scale

The lowest layer of earth's atmosphere is :

1. troposphere

2. stratosphere

3. mesophere

4. ionosphere

Ozone depletion in the stratosphere is mainly caused by:

1. SO₂

2. NO₂

3. NO

4. chlorofluorocarbons

Gas that is not a pollutant is : 

1. Carbon monoxide

2. Nitrogen peroxide

3. Carbon dioxide

4. Sulphur dioxide

Air pollution from the leakage of methyl isocyanate gas from the union carbide factory in Bhopal caused a major tragedy on:

1. Dec. 2, 1984

2. Dec 15, 1983

3. Dec.10, 1982

4. Dec. 4, 1988

Eutrophication of a lake means, it:

1. is low in nutrients

2. is high in nutrients

3. has a high temperature

4. has an lesser amount of organic matter

Which of the following gases present in air protects life on the earth from the harmful effects of UV rays from the sun?

1. Carbon dioxide

2. Nitrogen

3. Oxygen

4. Ozone