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问题 填空题

右图为静电场的电场线分布图的一部分，A、B、C、为电场中的三点，比较这三点的场强大小EA，EB，EC，它们由大到小的顺序是            。

答案

EA＞EB＞EC

由电场线的疏密程度反应场强大小，所以EA＞EB＞EC

完形填空

阅读下面材料，用不多于3个单词的正确形式填空

Are you facing a situation that looking impossible to fix?

In 1969, the pollution is terrible along the Cuyahoga River near Cleveland, Ohio. It ______小题1:(be)imaginable that it could be ever be cleaned up. The rive was so polluted that it ______小题2:(actual) caught fire and burned. Now year late,this rive is one of_______小题3:most outstanding examples of environmental cleanup.

But river wasn’t changed in a few days_____小题4:even a few months. It took years of work _______小题5:(reduce) industrial pollution and clean the water. Finally, that hard work paid off and now the water in the river is______小题6:(clean) than ever.

Maybe you are facing an impossible situation. Maybe you have a habit _____小题7:is driving your family crazy. Possibly you drink too much or don’t know how to control your credit card use. When you face such impossible situation, don’t you want a quick fix and something to change immediately.

While there are_______小题8:(amaze) stories of instant transformation, for most of us the  _______小题9:(change) are gradual and require a lot of effort and work, like cleaning up a polluted river. Just be_______小题10:(patience)
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单项选择题

纯金一般指成色达到（）以上的黄金。

A、99.5%

B、99.0%

C、99.6%

D、99.99%
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