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问题 填空题

为了既可以省力，又能改变________ ，可以把_________和________组成滑轮组，使用滑轮组时，轮组几段绳子吊着物体，提起物体所用的力就是物重的________ 。如图所示，物体A重为100N，挂重物的钩子承受的拉力是_______ N，人匀速拉绳子的力是______N （动滑轮自重、摩擦和绳重均不计）。

答案

力的方向；定滑轮；动滑轮；几分之一；100；50

单项选择题

入射光线被两种介质的分界面（）反射到原来的介质中，这种现象叫全反射。

A.全部

B.大部分

C.极少
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问答题

Passage 1 The message I wish to convey to you is that I have complete confidence that Beijing will deliver an outstanding Olympic Games in 2008, that this will be a wonderful event for China and for the world, and that it is already serving to strengthen the very close relations between Australia and China. My own association with the Beijing Games began with Beijing’s bid. For me and for a number of Australians, the opportunity to support and assist the bid was far more than simply an interesting professional exercise. It was an opportunity to do something important.// We believed then, and we believe now, that hosting the biggest and best people-to-people event on the world’s calendar will give further momentum to the process of modernization in China and the friendly integration of China with the world community. The purpose of the Games is of course not geopolitical; it is to conduct a celebration of sport and culture. But, as we know from our own experience with both the Melbourne Games in 1956, when Australians reveled in that first historic opportunity to welcome the world to our shores and Sydney in 2000, when we were able to show the world the dynamism of modem Australia, the Games can and do leave a wider and powerful legacy.// So it will be for China in 6 years time. The legacy will in part be of a tangible kind -- world-- class venues and other civic buildings, the Olympic Green, increased trade, investment and business relationships. Beijing’s plans for these tangible legacies are impressive both in their ambition and in the determination of the organizers to bring them to fruition. But perhaps even more important in the long run will be the intangible legacy of the 2008 games. I refer here to the heightened consciousness of the importance of the environment, already a high national priority in China but one which is certain to be reinforced by the commitment to the Green Games.// An enduring memory for me from the days of the Beijing bid is the sheer delight of people in China, especially young people, at having the chance to play host to athletes, officials and visitors from around the world, to welcome them to China, to show them China and to build new friendships. International relations are not only about the conduct of political and economic affairs between governments and businesses. It must also be underpinned by the sort of deep international understanding that can only come from closer and closer relationships between peoples.// The Olympic Games are the most successful and popular embodiment of internationalism ever invented by human beings. During these glorious days, we will show how we can, at our best, transcend all differences of country, race and religion and truly embrace the common humanity that binds us all together. The participation of 1.3 billion people in that great goal can have profound and enduring benefits for our Asia-Pacific region and for the world. The Olympics are therefore coming to China at exactly the right time in terms of the changes underway in China itself and in terms of China’s engagement with the region and the world.//
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