Ground water is the____________source of water for man.

Areas that receive large amount of rainfall have the problems of flood and marshy lands in:

Supply of water to farms is called :

___________are often used to transport logs.

Heavy rainfall leads to :

Large amount of _______________is buried in the ocean floor.

The store house of many resources like fish,minerals and energy is______.

Area that slopes down on drains to the main river is called:

The process of changing water in to its vapour is called:

Acid rain is a type of __________pollution.