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在我国“嫦娥一号”月球探测器在绕月球成功运行之后,为进一步探测月球的详细情况,又发射了一颗绕月球表面飞行的科学试验卫星.假设该卫星绕月球做圆周运动,月球绕地球也做圆周运动,且轨道都在同一平面内.已知卫星绕月球运行的周期T0,地球表面处的重力加速度g,地球半径R0,月心与地心间的距离r,引力常量G,试求:
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    In February of 2005, Phil Belfiore was teaching one of Robert Frost's poems “Stopping by Woods on a Snowy Evening.” He liked it that he recorded it on his home answering machine, which would lead to one of the most unusual1of his life.

    When Phil returned from his vacation, he listened to his voice 2  One gentleman caller 3for dialing the wrong number. But, he added, he'd really 4the poem. Phil laughed and thought nothing more of it— 5the phone rang a few days later.

    Phil 6John's hollow voice immediately, who said sorry to7, but he was calling to hear the8again. The two men talked. It turned out that his brother's phone number was9from Phil's by one digit(数字), thus the wrong number. Before hanging up, Phil told John to 10anytime, whether to hear the poem or just to have a chat.

    That was 11 years ago. They've spoken on the phone a few times a month ever since. It is John who is 11the starter of most calls. However, Phil will ring if a long while has passed. Not 12  John has been in poor health. His special voice is just the 13of some heart trouble. They seem to always 14when there's been a big sports event. The man like to discuss 15most. John will also 16Phil on his life. Slowly, their conversations have grown much more 17  When asked what drew them together, Phil18that they were old friends. They planned to meet twice, but circumstances went19them. Their friendship is based on the simple act of picking up the phone. “My best friend is someone I've not yet met 20 ” says John. It's as simple as that.