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问题 填空题

质量为m的人造卫星沿一圆形轨道运动，地球半径为R，卫星距离地面的高度为2R，地球的质量为M，则卫星的动能为（）.

答案

参考答案：

解析：

本题考点在2010年4月真题第一大题第5小题考查过，主要考查的知识点为万有引力提供向心力的相关计算。

卫星受到的引力为向心力

单项选择题

物业服务企业因维修物业或者公共利益需要确需临时占用、挖掘道路、场地的，也必须征得（）的同意，不得擅自施工，无论业主或物业服务企业临时占用、挖掘道路、场地，均应当在约定期限内恢复原状。

A、业主委员会

B、居民委员会

C、建设主管部门

D、物业服务企业
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单项选择题

Expressing gratitude is an important form of good manners. Nowadays more and more people in China have found it’s high time to (1) a thankful heart for the young.Everyone likes to get praised and appreciated. Gratitude is the greatest of virtues, which lets others smile and makes the world more beautiful. You just need several minutes to write down a thank-you note, but it brings much joy to the (2) .We live in a society where we enjoy the different services of others. But (3) of them should be taken for granted.Gratitude is also a kind of (4) in life. In developing gratitude for every moment—for the simple joys and even for the (5) times—we come to truly enjoy and appreciate life. Then we are able to see the (6) that surrounds us.Try to write a thank-you letter to your parents for working hard to (7) you a happy life.Be grateful to your teachers because of their (8) with your studies and character building.Say thanks to your friends who (9) both your happiness and sorrow. We are sure it will bring them much joy and add (10) into your own life as well.

第（4）空应选择（）

A．attitude

B．feeling

C．emotion

D．sense
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