阅读下面短文，从每题所给的四个选项中，选出一个最佳答案.

　　There are different ways in which people try to deal with the problem of energy. One way is the greater production of common energy sources (能源) such as coal oil and gas. The trouble with these sources however is that they are not renewable.

　　Another way is energy conservation (节能) which means using energy more efficiently (有效地). In some very cold countries people build special houses to save energy. They place materials between the inside and the outside of the walls of the house to keep the cold out and the warmth in. The house is heated by the lights the body heat of the people and the other equipment in it.

　　Finally renewable energy sources are used even though they are often expensive to develop. One form of these is geothermal energy . In certain parts of the world the temperature of the earth increases thirty degrees centigrade with each kilometre down. At six kilometres therefore it rises to nearly two hundred degrees. To get the heat water is pumped (压 抽)down into the rocks and back up to the surface. Heat from the earth is already used in certain countries.

(1)How many ways of dealing with the energy problem are discussed in the text?

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(2)From the text we learn that coal ________.

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A．is quite easy to produce

B．is not used most efficiently

C．is the most common source of energy

D．could be renewed only by new technology

(3)The writer tells about the “special houses” because they ________.

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A．show the excellent skills of the builders

B．serve as an example of energy conservation

C．are heated by different sources of energy

D．are warmer than other types of houses

(4)The underlined words geothermal energy in the third paragraph mean

______.

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A．renewable source

B．underground source

C．heat inside the earth

D．temperature of the earth

(5)Which of the following drawings shows the right way to get geothermal energy?

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(6)At a place where surface temperature is 15℃ how deep do you have to dig so as to get a temperature of 75℃?

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