2. Answer the questions:
1- Water is one of the commonest of all substances, and without it life would be impossible.
2-The seas and oceans cover about seventy per cent of the Earth's surface but water is also contained in the soil, in the atmosphere and in all living things.
3-More than half of the human body consists of water.
4- In food we eat , especially vegetables and fruit
5- Water exists as a substance in three states: ice, which melts at 0˚ degrees Centigrade; liquid water and steam, the latter is formed when water boils at 100˚ degrees Centigrade.
6- Water differs from other liquids. It expands when cooled from 0˚ Centigrade, contracts when heated from 0˚ to 4˚ Centigrade, and reaches its maximum density at 4˚ Centigrade. No other liquid possess this property. Pure water is rarely found in nature. This is because water is able to dissolve so many substances from the air, the soil and rocks.
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