题干

海水淡化可有效解决人类的用水问题,淡化海水的方法有很多种,其中一种是“蒸馏法”,即将海水中的水蒸发出来,再将水蒸气冷凝成液态淡水,以上过程涉及的物态变化有(  )

A:汽化和凝固

B:汽化和凝华

C:汽化和液化

D:升华和凝华

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答案(点此获取答案解析)

C

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    One day a rich man was invited to dinner at the home of one of his friends. He did not know what “to1the wine, meat and chicken he had just bought.” Certainly he could not2them to the servant. Then he had3 idea. He called up the servant and4to him.

     “I'll be away for the whole evening, and I'll leave you to look after the house. In the cupboard there are two bottles filled with5 Be careful about it. You'll be killed if you take even a6of it. There is also some meat and chicken in the cupboard. Take care of them.”7these words the rich man left the home.

    8the master turned his back, the servant opened the cupboard and began to enjoy all the nice things in it. He 9the two bottles and ate up the meat, the chicken and10he found in the cupboard.He was11and soon fell12

    At mid- night the rich man returned home. He looked into the cupboard and to his great13 all his wine and food were14 He was mad with15and called the servant up. “Oh, Master,” the servant began to say16the rich man could open his mouth; “while you were away, the neighbor's black cat stole into our kitchen and ate up everything in the cupboard. I know you would be angry with me. I was so17that I drank the two bottles of poison to kill18” There were tears in the servant's eyes. “Oh, Master,” he continued, “Please don't get angry with a 19man. I'll soon be dead." The rich man, of course, did not20a word of his story. But again, he could do nothing about it.