Q.V. Expand any one of the ideas.
1. Water a precious resource. 2.Laughter is the best medicine.
Answers
Water a precious resource
Water is a renewable natural resource. It is a vital body fluid which regulates life-processes such as, digestion of good, transportation of nutrients and excretion of body wastes etc. It is also required for the germination of seeds. Water is an important participant of photosynthesis.
Water provides habitat to many animals and plants. All animals and plants living in water are adapted to live in water.
There is.eniugh fresh water on the earth to meet our present requirements. But there is a golbal shortage of usable water. At many places, there is an acute shortage of water. It is estimated that a few years from now, more them one-third of the people on our earth will not get sufficient water to live.
The water table is falling in most areas. If something is not done to check it, soon we will be facing water-crisis. To prevent it, we should save water. As a part of community efforts in this direction, water-harvesting is being encouraged.
How much water is available?
About 71 percent of earth's surface is covered with water. About 97.4 per cent of the total water on the earth is in oceans and seas. The water in oceans and seas cannot be used for drinking, domestic use, irrigation and industrial use because it contains many salts.
The relative propogations of different kinds of water are shown alongside.