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问题 单项选择题

人的思维与安全行为有密切关系。思维就是以已有的知识经验为中心，对客观现实的概括和间接的反应。下列特征中，不属于思维特征的是( )。

A．广阔性

B．批判性

C．逻辑性

D．持久性

答案

参考答案：D

选择题
将1.12g铁粉加入25mL 2mol•L-1的氯化铁溶液中，充分反应后，其结果是（　　）

A．铁有剩余，溶液呈浅绿色，Cl-浓度基本不变

B．往溶液中滴入无色KSCN溶液，显黄色

C．Fe2+和Fe3+的物质的量之比为6：1

D．氧化产物与还原产物的物质的量之比为2：5
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完形填空

Enough sleep is important to health. The amount of sleep __1________(need) depends on the age of the person and the conditions in _2.________ sleep takes place. The young may need more sleep than __3.________ old, but usually eight hours are enough for the health of grown-ups. Some can do with ___4_______ than this amount, but others may need more. Every person knows his own need. ___5_______ is then a matter of good judgment to satisfy his need. Sleep should always be enough to make one bring back his __6.__________ (strong) and get ready for a day’s work.

Fresh air is necessary to sound sleep. So it is not __7.___________ reason for some people to think that it is practicable to sleep in the open air. A bath at bedtime, __8._________ hot nor cool but of body temperature, may be helpful_9._________ sleep. Sleep-producing drug should never be taken except when _10.________ (suggest) by a doctor.
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