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Text 4
In modern industry, water fulfills several essential functions. It is used as a raw material in many processes; it is essential for cooling machinery; it provides steam for engines which consume coal and it is one of the most important sources of power.
As a source of power, water is virtually inexhaustible. Its power is ultimately derived from the force of gravity and from the sun. It is the sun’s energy that warms the sea and the land and causes water to evaporate into the air; later the moisture in the air condenses and falls in the form of rain or snow. Much of the water that falls on the land flows back to the sea. The downward flow of the water exerts considerable pressure, and it is at this point in the water cycle that we can capture some of its power.
The earliest method of exploiting this power was to make water turn a wheel. This system in which the force of water was used directly, had one great disadvantage. Factories which
A. In regard to hydroelectric power, Japan is lucky to have abundant rainfall and dense concentration of population.
B. No other countries in the world have developed their resources of hydroelectricity to such an extent as Japan.
C. Some other Asian countries have also develop their resources of hydroelectricity.
D. Japan developed their resources of hydroelectricity greatly compared with America.