劳动卫生学是预防医学的一个()。 A.三级学科 B.分支学科 C.子学科 D.一级学

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问题:

劳动卫生学是预防医学的一个()。

A.三级学科

B.分支学科

C.子学科

D.一级学科

E.重要学科

考点:放射卫生(医学高级)劳动卫生与职业病学劳动卫生与职业病学题库
题型:单项选择题

EPKS中的()是一个数据库点,代表了一组特定报警。

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关于磁感应强度的理解,以下说法正确的是

A.由B=F/IL可知,电流为1A、长为1m的通电导线在匀强磁场中受力为1N时,则匀强磁场的磁感应强度大小就是1T  

B.磁场中一小段通电导线所受安培力的方向就是该点磁感应强度的方向

C.小磁针在磁场中静止时北极所指的方向就是该点磁感应强度的方向

D.磁场中某点的磁感应强度与该点是否放通电导线无关

题型:单项选择题

下列关于常见有机物的说法不正确的是[ ]

A.乙烯和苯都能与溴水反应

B.乙酸和油脂都能与氢氧化钠溶液反应

C.糖类和蛋白质都是人体重要的营养物质

D.乙烯和甲烷可用酸性高锰酸钾溶液鉴别

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规定的允许故障率(),产品的使用寿命就长,规定的允许故障率(),产品的使用寿命就短。

A.高;低

B.低;高

C.大;小

D.小;大

题型:单项选择题

Dear Mom, Clear My Calendar

September is around the corner, and some of us are already complaining about summer’s end. But parents have a special reason to do so. The end of summer means the start of school. And these days, planning a young child’s schedule is a big challenge. The challenge is no longer finding activities to fill a child’s day; it is saying no to the hundreds of options available. Our mailbox is filled with brochures urging us to sign our kids up for classes from cooking to martial arts(武术).

Educators are themselves discouraged by the number of special classes that many children attend. In the name of “enrichment,” three-year-olds not only go to preschool in the morning but study French or gymnastics after lunch. One teacher tells of a four-year-old asking for help in the toilet before hurrying off to tennis. Another teacher says that children sometimes hold on to her at pickup time. What happened to unstructured time?

A generous explanation is that we enjoy giving children opportunities we never had. The truth however is that many parents have doubts about how much time they spend away from their families. And one way to reduce this guilt is to believe that time spent in these classes is somehow more beneficial to children than the time we know we should be giving them ourselves.

David Elkind, an expert on children, suggests that the 1960s gave birth to the belief that earlier is better. Parents hope that early music lessons, for example will build a child’s confidence. The truth, however, is that any time children are asked to do too much, too soon, they are at greater risk for feelings of failure.

A child’s time does not have to be planned to be meaningful. Remember the lazy days of summer? Some children sleep late and play with the kids across the street until it’s time to come home for dinner. However, with the majority of mothers working, fewer children enjoy that idle (空闲的) time now.

Come September, children across the country will finish a full day of kindergarten, only to attend an after-school program until 6 P.M., when a working mom or dad comes to take them home. That’s too much for a five-year old. Finances, of course, do limit some parents. But let’s be honest with ourselves – our own busy schedules, whatever they involve, are no excuse for burdening a young child’s.

小题1: The author holds that it’s a challenge to plan a schedule for a child mainly because _____.

A.a child’s schedule is too complex

B.activities suitable for kids are limited

C.parents are stuck in numerous choices

D.children always say no to parents’ advice小题2: What the two teachers say in Paragraph 2 implies that _____.

A.children love to stay at school

B.they are popular with children

C.children dislike after-school classes

D.after-school classes are of poor quality小题3: According to the author, what is the real reason for parents to send their children to after-school classes?

A.Parents want to make up for their own regrets.

B.After-school classes develop children’s potential.

C.Parents have doubt about their own ability to guide children.

D.After-school classes give parents an excuse for being absent.小题4:Which of the following will the author probably agree with?

A.For children’s benefits, the earlier the better.

B.Children’s spare time should be carefully designed.

C.Idle time for children is becoming a thing of the past.

D.Parents should be forgiven if they have a good reason.,

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