已知正方体ABCD-A1B1C1D1. (1)求证:平面A1BD∥平面B1D1C 发布时间：2017-05-15 23:22 │ 来源：www.tikuol.com 题型：解答题 问题： 已知正方体ABCD-A1B1C1D1. (1)求证:平面A1BD∥平面B1D1C;(2)若E、F分别是AA1、CC1的中点,求证:平面EB1D1∥平面FBD.
题型：解答题 下列说法正确的是（ ）A．动量的方向一定跟物体的速度方向相同，且动量大的物体其速度一定大B．冲量的方向一定跟对应的作用力方向相同，且冲量大对应的作用力一定大C．物体受到的冲量方向与物体末动量的方向不一定相同D．合外力的冲量为零，则物体所受各力的冲量均为零 查看答案
题型：解答题 完形填空。 The purpose of a letter of application (求职信) is to help you to "sell" yourself. It should state 1 thejob you want, and should tell what your abilities are and what you have 2 . It should be simple, human, personal and brief without 3 out any necessary facts. In writing a letter of application, keep in 4 that the things a possible employer is most 5 to want toknow about are your qualifications(条件), your achievements and your aims. The opening paragraph isperhaps the most important part. 6 the first few sentences fail to 7 the reader's attention, the rest ofthe letter may not be 8 at all. Try to key your opening remarks to the needs or interests of the employernot 9 your own need or desires. For example, instead of beginning with "I saw your 10 in today'snewspaper," you might say "I have made a careful 11 of your advertising during the past six months" or "I have made a survey in my neighborhood to find out how many housewives 12 your product and whythey like it." Try to 13 generalities. Be clear about the kind of job for which you are now 14 . College graduates looking for their first positions often ask "What can I 15 in a letter? Employers want experience-which, naturally, no 16 has." The answer is that everything you have ever done is 17 . It is important to write a good strong closing for your letter. 18 a specific request for an interview or givethe possible employer something definite to do or expect. An excellent 19 is to enclose(内附) a stamped, self-addressed envelope with your letter. That makes it 20 for a possible employer to get in touch withyou.( )1.A. clearly ( )2.A. found ( )3.A. sending ( )4.A. brain ( )5.A. probable ( )6.A. While ( )7.A . pay ( )8.A. kept ( )9.A. to ( )10.A. advertisement( )11.A. watch ( )12.A. change ( )13.A. avoid ( )14.A. losing ( )15.A. offer ( )16.A. worker ( )17.A. success ( )18.A. Make ( )19.A. result ( )20.A. happier B. carefullyB. done B. taking B. sight B. possibleB. AlthoughB. win B. continuedB. for B. report B. search B. make B. remember B. applying B. supply B. beginnerB. developmentB. Ask B. decision B. easier C. obviouslyC. known C. leaving C. order C. likely C. As C. show C. written C. into C. article C. study C. sell C. protect C. preparing C. mean C. owner C. practice C. State C. promise C. cheaper D. easily D. heard D. picking D. mind D. able D. If D. fix D. read D. from D. introductionD. discussion D. use D. gain D. fitting D. provide D. manager D. experience D. Get D. idea D. safer 查看答案