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问题 单项选择题

常用的脱脂剂中，既有毒，又易燃易爆的脱脂剂为（）。

A．工业用二氯乙烷

B．工业用四氯化碳

C．工业酒精

D．稀盐酸

答案

参考答案：A

解析：

二氯乙烷和四氯化碳都有毒，二氯乙烷和酒精易燃易爆，稀盐酸有腐蚀性，易燃易爆，且不是常用的脱脂剂，故选A。

阅读理解

This is a story from a meeting held by some people and two things in nature. We call it the Four-Sided Talk. Let’s “listen to” everyone carefully and find out what they think.

People: We have lived on the earth since ancient times. The earth is our home. Now we regret what we have done to our home!

小题1:What’s the United Nations’ decision in the Four-Sided Talk?

A．Set an Earth Day.

B．Find out what is making the pollution.

C．Hold an international meeting.

D．Protect and love the earth.小题2:What doesn't the old tree tell us?

A．He’s afraid to be cut down some day.

B．The trees have the longest lives in the world.

C．Over-cutting teaches people a lesson.

D．People are destroying the natural environment.小题3:What will people do according to the passage?

① Over-use the resources. ② Beautify the earth.

③ Start a global group.   ④ Protect the earth.

A．①④

B．②③

C．①③

D．②④
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多项选择题

血浆粘度增高见于（）

A.多发性骨髓瘤

B.原发性巨球蛋白血症

C.纤维蛋白原增高症

D.贫血

E.高脂血症
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