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问题 选择题

石棉的熔点高，又不易燃烧，可制作石棉网．石棉的化学式可表示为CaMg3Si4O12，其中硅元素的化合价为    [ ]

A．+1

B．+2

C．+3

D．+4

答案

答案：D

改错题

短文改错（满分10分）

I often quarrel about my mother over whether I can watch TV after school. She holds view that senior three students have to make fully use of every minute to work hard at their lessons. It seems to me that once I am allowed to do that, I’ll unable to control myself and forget all about my study. She also thinks it is bad for my eye. But I really can’t accept her ideas. In my opinion, watch TV can set my mind at rest after a day’s hard works. Besides, it is important for us to know what had happened at home and at abroad. Thus, we shouldn’t be forbidden to watch TV.
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判断题

妊娠晚期孕妇体重每周不应超过1kg。()
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