题干

关于简单机械,下列说法正确的是(   )

A:啤酒瓶起子是一个省力杠杆,可以省距离

B:滑轮组既可以省力又可以省功

C:船桨是一个费力杠杆,手移动较小的距离,船桨就可以移动较大的距离

D:动力臂越长的杠杆越省力

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C

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The Shirt of a Happy Man

    Once upon a time, in a rich and beautiful country, there lived an unhappy king. He slept 1and didn't feel like eating. The queen and his people worried about him very much. One day, a doctor was called in to examine the king. But he couldn't find 2 with his body. It was all in his mind. He said the king needed the shirt of a happy person to wear. Then the prime minister, the king's banker and the palace singer were called to the palace. But they all had3worries. They weren't happy, either. The prime minister thought many people were trying to 4, then he would lose his power. The banker was afraid 5 his money. The singer said he couldn't get freedom because he always worried about being followed by 6.

    7, the king's top general was told to go out and find a happy man in three days' time.

    Two days passed, the general still couldn't find a happy man. Everyone had their own problems, Just as he was about to give up, he saw a poor man8happily on the street. The general didn't understand why the poor man was so happy, though he seemed to have 9 power, money or fame. So he went up to the poor man and asked him about the reason. The poor man said he was happy because he had everything he wanted, and he didn't want to have what he couldn't have. Hearing this, the general was excited. The poor man was the Happy Man. So he asked the poor man to give his shirt10the king. "Shirt?" said the poor man in surprise, “I don't own any shirts!”