21.
If you want to keep an object cool while exposed to direct sunlight,

22.
Man and biosphere programme is affiliated with

23.
Succession initiated on large sand deposits or deserts is called

24.
The famous Minamata disease in Japan is due to the accumulation of____________in fishes.

25.
All are insitu conservation efforts except

26.
_________ is an on-site conservation method.

28.
On the average, about what percentage of the solar energy that strikes the outer atmosphere eventually reaches the earth's surface?

30.
If the absolute temperature of an object doubles, the maximum energy emitted goes up by a factor of: