滴定管活塞密合性检查操作为：在活塞不涂凡士林的清洁滴定管中加

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问题单项选择题

滴定管活塞密合性检查操作为：在活塞不涂凡士林的清洁滴定管中加蒸馏水至零标线处，放置（）min，液面下降不超过1个最小分度者为合格。

A.15

B.30

C.1

D.5

答案

参考答案：A

填空题

单词拼写。

1. The students went c______ when their team came first at the football match.

2. The policeman followed the person whose ______ (行为) was so strange for a while and then caught him.

3. This kind of pop music is popular with the ______ (青少年).

4. I had better say a few words by way of ______ (解释)

5. I think that you should accept the plan without ______ (争辩).

6. Children are ______ (禁止) to smoke.

7. The tsunami (海啸)______ (毁坏) many trees and buildings so that the local people lost their homes.

8. He wastes so much of his valuable time ______ (聊天) on line.

9. The village where they live is very ______ (令人厌倦的,乏味的).

10. I want to do things that ______ me (感兴趣).

名词解释

Enkephalin脑啡肽