The percentage of salt water on earth is

The human body is composed of about how much water?

These form integral part of basic organic compounds of life.

The element that is abundantly present in atmosphere is

Nitrogen makes its way back into the atmosphere through a process called

It is responsible for maintaining the earth as a greenhouse with temperature conditions suitable for life.

The main reservoirs of carbon are

These are poisoned by elemental oxygen

Decomposition of organic waste requires

The layer extends from the earth’s surface up to about 10 kilometers in altitude is