试题与答案

2012年1月27日广西龙江河镉超标,严重威胁着下游民众的饮水安全。为处理镉污染

题型:选择题

题目:

2012年1月27日广西龙江河镉超标,严重威胁着下游民众的饮水安全。为处理镉污染,当地政府组织人员在镉超标水域投放了大量烧碱或石灰,以及氯化铝,絮凝沉降镉离子,避免被人体吸收。则下列说法错误的是 [ ]

A. 此事件已对环境造成污染            

B. 镉是人体必需补充的微量元素 

C. 烧碱是氢氧化钠的俗称              

D. 烧碱和熟石灰都是碱

答案:

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参考答案:A解析:此题考查是否了解听力学中以dB为单位的数种声强级之间的区别,声压级是拟计量声音的声压(P)与参考声压(P0,规定P0=20μPaRMS)两者比值的对数,单位为dB(SPL);听力级是参考听力零级计算出...

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题型:情景交际

情景对话

     根据对话情景和内容,从对话后所给的选项中选出能填入每一空白处的最佳选项。

选项中有两个为多余选项。

Crystal: Hi, I just had a very interesting experience.

Jimmy: What is it?

Crystal:     1     It is the first day of my one-week program.

Jimmy: That sounds like fun.

Crystal: Yes, it was fun…but tiring! Kids are so energetic.

Jimmy:    2    

Crystal: At the primary school down the street. I visited some of their classes in the morning, and then taught them some simple English in the afternoon.

Jimmy: English must be very difficult for them.

Crystal:    3     I was quite impressed.

Jimmy: What did you teach them?

Crystal: One teacher asked me to practice some sentences.     4    

Jimmy: That’s great. You know, when I was in primary school, we never had English lessons.

Crystal: How about in middle school?

Jimmy:    5   It wasn’t very practical.

Crystal: Well, but you’ve managed to learn English very well.

A.I spent the whole day with dozen of little children!

B.I helped my aunt look after her child at home.

C.Yes, they find t hard to learn.

D.Where did you meet all these kids?

E.We studied English, but only for tests.

F.Actually, they were very eager to learn.

G.We also played some English games together.

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