题目内容
已知平面区域D1={(x，y)|x²+y²≤9}，D2={(x，y)|(x-x0)²+(y-y0)²≤9}，D2覆盖区域的边界长度为8π。（）（1）x0²+y0²=9；（2）x0+y0+3。
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阅读下面的文字，根据要求作文。请结合实际写一篇700字左右的论说文。 上世纪中叶，美国的波音和麦道两家公司几乎垄断了世界民用飞机的市场，欧洲的飞机制造商深感忧虑。虽然欧洲各国之间的竞争也相当激烈，但还是采取了合作的途径，法国、德国、英国和西班牙决定共同研制大型宽体飞机，于是“空中客车”便应运而生。面对新的市场竞争态势，波音和麦道于1997年一致决定组成新的波音公司，以抗衡来自欧洲的挑战。
B December 25，2006 Dear Rose， How are you I like your programmes very much．They’re very interesting and I can learn a lot from them．I like travelling and I have won a free four—week trip to England，but I know little about the British way of life．Would you please write to tell me something about the British meals Thank you． Yours， Wang Lin January l，2007 Dear Wang Lin， It’S very helpful to know something about the British meals before travellin9．In many English houses，people eat four meals a day．They are breakfast，lunch，tea and dinner． Breakfast takes place at any time from 7：00 t0 9：00 in the mornin9．They usually have eggs，bread with butter，cheese and SO on．English people drink tea or coffee at breakfast．Lunch comes at one o’clock．It can be a hamburger or a three—course(三道菜)meal．Afternoon tea is between 4：00 pm and 5：00 pm．Dinner begins at about half past seven．The first course is soup．The next is often meat or fish with vegetables．Then come fruits of different kinds：apples，pears，bananas and so on．But not all English people eat like that．Some of them have their dinner in the middle ofthe day．Their meals are breakfast，dinner，tea and supper．And all these meals are usually simple． Wish you a good time in England! Yours， Rose The possible time for breakfast in England is （） ．
C Learning l-low to Learn$22 Children who read this book show great interest in study．Many pictures will help them an-derstand it easily and quickly． The Basic Study Guidebook$36 Read this book and learn：What the three barriers(障碍)to study are and what to do about them What to do if you are tired of a subject Children read it to improve the ability to study． How to Use a Dictionary Pict-lre Book for Children$35Read this book and leal’n：How to look up words in a dictionaryWhat the different marks in a dictionary meanHow to use a dictionary to pronounce words correctlyBuy this book and help children unlock their education．What’S more，you’11 just pay 60％for itbefore May l0，2009． “ ”can tell you what to do if you are tired of a subject．
Questions 11 to 13 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions. Now, listen to the passage. In the old days dogs were used for the following EXCEPT （）
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