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下表是某一植物在一天中某些时段的失水量，请分析回答：

时间（时）
失水量（克）
7：00-8：00
190
9：00-10：00
209
11：00-12：00
221
13：00-14：00
233
15：00-16：00
227
17：00-l8：00
213
19：00-20：00
190
21：00-22：00
100
23：00-24：00
90

（1）尝试给出反映此植物失水情况的曲线图。（2）怎样解释表中显示的现象？从中可以得出什么结论？

答案

（1）“略”

（2）7：00-14：00，随着气温的升高和光照的增强，植物的蒸腾作用逐渐加强；15：00-24：00，随着温度的降低和光照的减弱，蒸腾作用逐渐降低。植物体的蒸腾作用受温度和光照的影响。

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盘式制动器所产生的制动力矩的大小与油压的大小成正比关系。
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As the Net pushes the economy (57) rapidly, the economy is also bringing the Net market forward, resulting in the Internet itself becoming the world’s largest emerging market. Of course, this is just the beginning. Although there are many companies which made huge profits (58) in the Internet market, they tend to be small companies. To date, most companies are making losses. The competition in the knowledge-based economy will also be more (59) This will definitely promote (60) and more efficient cooperation.

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A.ahead 

B.backward 

C.front 

D.behind
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