List three major impurities present in river water.

Answer the following questions in brief:

(a) In which form is water present in the atmosphere?

(b) Which source of water contains the highest concentration of salt in it ?

(c) What possible impurities does rain water contain?

(d) What is water table?

What is water cycle? State two important roles of water cycle in nature.

Give reason:

Rain water is considered the purest form of natural water.