如图所示,轻弹簧的两端各受20N拉力F的作用,弹簧平衡时伸长了5cm(在弹性限度

题型:选择题

问题:

如图所示,轻弹簧的两端各受20N拉力F的作用,弹簧平衡时伸长了5cm(在弹性限度内),那么下列说法正确的是(  )
A.弹簧所受的合力为40N
B.该弹簧的劲度系数k=200N/m
C.该弹簧的劲度系数k=400N/m
D.根据公式k=,弹簧的劲度系数k会随弹簧弹力F的增大而增大
考点:弹力的大小、胡克定律
题型:选择题

We live in the computer age. People use computers to do much of their work. But few people know how to look after them. Remember the following when you use your computer:

1.Keep your computer in a cool, dry room. Too much or too little heat is bad for computers. Damp(潮湿) is also bad for them.

2.Do not let people smoke near your computer. Smoke of all kinds is very bad for many parts of a computer.

3.Do not eat or drink when you are near your computer. Pieces of food and a little water in the keyboard are also bad for a computer.

4.Keep your screen clean and do not have it too bright. They are bad for your eyes. Make sure the screen is not too far from or too near your eyes. Some people use different glasses to protect their eyes when they use a computer.

小题1:Computers can          people to do a lot of work.

A.use

B.help

C.make

D.take小题2:Few people know how to          their computers.

A.look at

B.try out

C.look for

D.take care of小题3:A computer works well at a temperature of         .

A.0℃

B.-5℃

C.20℃

D.35℃小题4:Smoke is not good for many parts of a computer, is it?

A.Yes,it is.

B.No,it isn't.

C.Yes,a little.

D.Not at all.小题5:A dirty screen or a very bright screen is    for your eyes.

A.bad

B.good

C.useful

D.helpful

题型:选择题

医疗机构对医务人员考核要作为应聘、提薪、晋级以及评选先进工作者的首要条件应是( )

A.业务能力考核
B.服务水平考核
C.学历情况
D.医德考核结果
E.医疗质量考核

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构成小麦产量的主要因素是____。

A.单位面积穗数,每穗粒数,千粒重

B.单位面积株数,单位面积穗数,千粒重

C.单位面积株数,单位面积穗数,每穗粒数

D.单位面积株数,每穗粒数,千粒重

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()是现代人事行政制度的基础。

A.职位分类

B.绩效考核

C.工资福利

D.奖励惩处

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在项目风险管理的基本流程中,不包括下列中的()

A.风险分析

B.风险监控

C.风险规避措施

D.风险管理计划编制

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