问题
选择题
若条件p：log2x＜2，条件q：
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答案
由题意可得：条件p：log2x＜2，即条件p：0＜x＜4，
所以¬p：x≤0或x≥4；
因为条件q：
≤0，即条件q：1≤x＜4，x-1 x-4
所以¬q：x＜1或x≥4；
所以¬p⇒¬q，即p是¬q的充分不必要条件．
故选A．
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若条件p：log2x＜2，条件q：
|
由题意可得：条件p：log2x＜2，即条件p：0＜x＜4，
所以¬p：x≤0或x≥4；
因为条件q：
≤0，即条件q：1≤x＜4，x-1 x-4
所以¬q：x＜1或x≥4；
所以¬p⇒¬q，即p是¬q的充分不必要条件．
故选A．
完形填空 阅读下面的短文，掌握其大意，然后从各题所给的A、B、C和D选项中，选出最佳选项。（每小题2分，共30分） Computers have done us a lot since they turned up. In the future they will play a more important part in many __16__, such as education, transport, personal lives, scientific research and so on. Nowadays computers are being used in ___17__ and industry and can help the farmers to __18__ the conditions of the plants. More and more computers will come into our daily life with the __19__ of science and technology. If you want to change money or pay your electricity bills, you won’t have to go to the __20__. A computer and a telephone will help you. It can also help you to do the housework and it can even __21___ human voices and carry out the instructions. It is __22__ that the majority of the labor force will work at home. People will be able to use the videophone for conferences. This can help us to save a lot of energy and ___23__. It is said that trains in Japan will have no __24___, because they’ll be well __25___ by computers, which can also tell the best ___26__ between trains. Computers programs for __27__ whole texts are already well developed. You can ___28__ the name of a certain subject and a __29__ list of book titles will __30__ on your screen. You may choose whichever you want.
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