题干

匀速前进的车厢顶部用细线竖直悬挂一小球,如图所示,小球下方与一光滑斜面接触.关于小球的受力,说法正确的是(  )

A:重力和细线对它的拉力

B:重力、细线对它的拉力和斜面对它的弹力

C:重力和斜面对球的支持力

D:细线对它的拉力和斜面对它的支持力

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答案(点此获取答案解析)

A

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    My daughter had a bullying(欺凌) problem a couple of years ago. She kept receiving rude text messages from kids at school. Dealing with school bullying wasn't easy, but I finally ended it. When you realize things are serious, it is no time to be silent.

    If your kids are also receiving such text messages, take them directly to the headmaster and show him. Describe to him how it is affecting your kids. Tell him you will not tolerate it and that you want him to put an end to it now.

    School bullying is a dangerous and serious issue these days, and any good headmaster will take your charges seriously. He will probably address the issues with the parents. If they are crappy(糟糕的) parents, then they may do nothing to their child. You may have to repeat this process several times, but you need to keep a check on those text messages and don't allow your child to delete them.

    Now it is time to draw your child close and take care of him/her, because he/she needs it. My daughter did not like me being involved either, but you are the only person your kid can depend on to solve this problem, so do it and mean business. Always be polite, but straightforward. The headmaster and parents must know you mean business.

    If repeated meetings with the headmaster (and parents, if he allows it) do not work, then I would consider hiring a lawyer. That will send the message loud and clear. When you are talking about financial loss, most parents will stand up and take notice and act to keep their kids under control!

    I know a lawyer is a big expense and not something you do lightly, but when bad things like school bullying are happening to your children, you must act and act quickly.