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问题 选择题

已知石墨在一定条件下转化成金刚石是吸热反应，由此可能出的正确结论是（　　）

A．石墨比金刚石更稳定

B．金刚石比石墨更稳定

C．石墨转化成金刚石是物理变化

D．石墨和金刚石的结构相同

答案

A、石墨转化为金刚石要吸收能量，说明石墨的能量低，稳定，故A正确；

B、石墨转化为金刚石要吸收能量，说明石墨的能量低，稳定，故B错误；

C、金刚石和石墨是不同的物质，是化学变化，故C错误；

D、石墨和金刚石是两种物质，结构不同，故D错误；

故选A．

单项选择题

集体土地征收是指国家为了社会公共利益的需要，依据法律规定的程序和批准权限，依法给予农村集体经济组织及农民补偿后，将农民集体所有土地变为国有土地的行政行为。下列关于征收集体土地的表述，正确的是（）。

A．由集体土地所有者与土地使用者签订土地出让合同

B．由市县人民政府与土地使用者签订土地出让合同

C．由市县人民政府土地管理部门与土地使用者签订土地出让合同

D．集体土地不经征收不得出让
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单项选择题

For the people who have never traveled across the Atlantic the voyage is a fantasy. But for the people who cross it frequently one crossing of the Atlantic is very much like another, and they do not make the voyage for the (56) of its interest. Most of us are quite happy when we feel (57) to go to bed and pleased when the journey (58) . On the first night this time I felt especially lazy and went to bed (59) earlier than usual. When I (60) my cabin, I was surprised (61) that I was to have a companion during my trip, which made me feel a little unhappy. I had expected (62) but there was a suitcase (63) mine in the opposite corner. I wondered who he could be and what he would be like. Soon afterwards he came in. He was the sort of man you might meet (64) , except that he was wearing (65) good clothes that I made up my mind that we would not (66) whoever he was and did not say (67) . As I had expected, he did not talk to me either but went to bed immediately.
I suppose I slept for several hours because when I woke up it was already the middle of the night. I felt cold but covered (68) as well as I could and tried to go back to sleep. Then I realized that a (69) was coming from the window opposite. I thought perhaps I had forgotten (70) the door, so I got up (71) the door but found it already locked from the inside. The cold air was coming from the window opposite. I crossed the room and (72) the moon shone through it on to the other bed. (73) there. It took me a minute or two to (74) the door myself. I realized that my companion (75) through the window into the sea.

A. draft B. voice C. air D. sound
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