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如图甲所示,倾角θ=37°的粗糙斜面固定在水平面上,斜面足够长.一根轻弹簧一端固定在斜面的底端,另一端与质量m=1.0kg的小滑块(可视为质点)接触,滑块与弹簧不相连,弹簧处于压缩状态.当t=0时释放滑块.在0~0.24s时间内,滑块的加速度a随时间t变化的关系如图乙所示.已知弹簧的劲度系数k=2.0×102N/m,当t=0.14s时,滑块的速度v1=2.0m/s.g取l0m/s2,sin37°=0.6,cos37°=0.8.弹簧弹性势能的表达式为Ep=
1
2
kx2(式中k为弹簧的劲度系数,x为弹簧的形变量).求:
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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.