对采样精密度要求最高的是（）A．洗煤； B．原煤； C．精煤

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.

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

A. help      B. make        C. use

小题2:Few people know how to_____ their computers.

A. look for   B. take care of   C. look at

小题3:A computer works well at a temperature of _____.

A. 0℃       B. 35℃        C. 20℃

小题4:Is smoking good or bad for many parts of a computer?

A. good      B. bad         C. I don’t know.

小题5:A dirty screen or a very bright screen is ______ for your eyes.

A. helpful     B. good        C. bad

社区居民委员会提供社区服务的方式包括（）。

A.了解服务需求

B.委托服务

C.反映群众意见

D.提供便民服务

E.服务热线

人力推车时1次只准推1辆，严禁在矿车两侧推车。同向推车的间距，在轨道坡度小于或等于（）‰时，不得小于10米，坡度大于（）‰时，不得小于（）米。

竞买人以报价方式向拍卖人所作的应买的意思表示，在法律性质上属于( )。

A．要约邀请
B．招标公告
C．要约
D．合同的确立

某人行走时，足部突然受到伤害性刺激，迅速抬腿。如图为相关反射弧示意图。

伤害引起的痛觉可通过下丘脑促进垂体释放（），直接促进（）对水的重吸收。