题干

如图所示是给墙壁粉刷涂料用的“涂料滚”的示意图。使用时,用撑竿推着粘有涂料的涂料滚沿墙上下缓缓滚动,把涂料粉刷到墙上.撑竿的重力和墙壁的摩擦均不计,且撑竿足够长,粉刷工人站在离墙壁一定距离处缓缓上推涂料滚,设该过程中撑竿对涂料滚的推力为F1,涂料滚对墙壁的压力为F2,则(     )

A:F1增大,F2减小     

B:F1增大,F2增大

C:F1减小,F2减小

D:F1减小,F2增大

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答案(点此获取答案解析)

C

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根据短文内容, 从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    Are you satisfied with your life? How often do you think of reasons why everyone around you is successful though they are not usually better than you? What do you do wrong? Here are some things you should stop doing to be successful.

1) ____

    Different people may interpret “success” in different ways: some of them measure it in money, other ones — in positive changes to people around them and the world.____ And do not worry about what other people think, and come after what makes you happy.

2)Do not believe anything without questioning it.

    ____ They are critical thinkers, and they understand that we are all ruled by our prejudices; so, they will always question new information.

3)Do not worry about all unpredictable things that may happen to you.

    If you want to be successful, stop thinking about everything that MAY happen to you.____ Be ready to change your deeds and decisions when things suddenly don't go according to your plan.

4)Do not care about what other people think of you.

    ____ Your attempts to become “good” for everyone will turn into nothing but new worries, stresses, and problems. Successful people do not concentrate on quantity of people to please, but worry about their quality and focus on developing friendships with people they really care about.

Success is good, but you should understand that life will get depressing without friendship and love.

A. Try to feel comfortable with the reality and accept the fact your future can't be predicted.

B. Do not let others decide what “success” is for you.

C. As far as we all know, it's impossible to please all the people who surround us.

D. Do not wait for the “right time” to do anything.

E. Successful people never ignore or avoid problems, no matter how big and awful they seem.

F. Successful people do not just accept any new information to be true.

G. If you want to be successful, do not let others force their interpretation of success on you.