The Montreal Protocol was signed in 1987 to:

1. prevent deforestation around the world
2. control the emission of ozone depleting substances
3. control the green house gases
4. prevent hazards from radioactive nuclear wastes

CFC have a continuing effect on ozone layer as:-

1. the Cl atoms formed by them only act as catalysts in reactions causing degradation of ozone

2. the Cl atoms formed by them are used up in reactions causing degradation of ozone

3. they are being produced in increasing amounts all over the world

4. they are efficiently absorbed by the atmospheric water vapors

Which of the following is not likely to happen as a result of the rising levels of ${\mathrm{CO}}_2$ in our atmosphere?

1. Increased incidents of skin cancer

2. Rise in sea levels

3. Change in climatic patterns

4. Shifts in locations of deserts and fertile regions

Depletion of which gas in the atmosphere can lead to an increased incidence of skin cancers
(1) ozone

(2) ammonia 

(3) methane

(4) nitrous oxide

Which of the following is not one of prime health risks associated with greater UV

radiation through the atmosphere due to depletion of stratospheric zone?

1. Increased skin cancer

2. Reduced immune system

3. Damage to eyes

4. Increased liver cancer