A: 选项C
B: 选项D
C: 选项B
D: 选项A
举一反三
- 下列化合物中苯环上取代基对苯环+C 效应大于-I效应的是（ ）[img=774x126]17d6087b129a1fd.png[/img] A: 选项C B: 选项D C: 选项B D: 选项A
- 下列系统中，_______是线性的。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/69188060fb4c48d68700d5224ce70e53.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/66e06f948fa34740a90a8c1cc227c6b6.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/4c264641de7b410e873171e90fd444ef.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/a3f710b25c2248b48ed5f6f1d342c078.png" />
- 下列信号中，____是能量信号。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/e8fc82c3d7b046fc949119acef31f0f0.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/6085f08fa59b45e0ac501f77d9e9ac5c.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/450d1385152b4c67a5ec0e2e7a8f50d7.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/7a668260d2ea405ea903fc344f3ea5bc.png">
- 下列信号中，______是因果信号。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/56c3db40bb36428688799a6164924c2b.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/c775ed12f5af47549261ce4b9ae7c969.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/1a1575aacbdf4e95882a87cf2a5a7049.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/48b1a932dc504373ab3bf0e87edb513a.png">
- 下列信号中，_____周期信号。 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/5f333529a6724b348f3719d4ad9cb2a7.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/baaca1beb7ea457eaf7544beec0fa639.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/2a8d2203eb2948ce8d95e650e32130f2.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/a2d52c07e1c54524b53b98cd92d39815.png">
内容
- 0
下列各组投影式中，两个投影式相同的组是（ ）<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/e2f6ffb6f27f4afbab7a80b2be9762db.png" /> A: 选项B B: 选项D C: 选项A D: 选项C
- 1
下列信号中，哪一个是非周期信号？ A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/83f68e76be124295b0983618abb2469a.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/0d9998b227e44cf9923532daf025311e.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/a67487615b1248bd9a7978fa581f8821.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/14e55c6393c74631a39866e1b8befc89.png">
- 2
读装配图中零件10，下列哪个图是正确的 （ ）<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/3e06ba277c804a0184232a92dc4daae8.png"/> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/f552fe75449e4a54ac92d376ccb56c4d.png"/> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/ceee8794adba4c09a22636cc1400760a.png"/> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/de760892beba4aa0b43f5ad85fa1a8e3.png"/> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/bd80973d489b4003904efdee208828b2.png"/> E: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/3206dcc5d56c4536b359f5b66ae1fe03.png"/>
- 3
下列卤代烃中哪些不能用于制备格氏试剂 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/8e4b1eddb7974957a9ea3b2108b82f94.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/0b5b9f82a0f240448d093df7d3f2f47a.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/f0972e4286ca44a3b598a774bd2ece7c.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/71069a506c07480bb0e9b25b1c7e015d.png" />
- 4
下列哪种情况属于存在序列相关 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/7677353003d1437481e2ce756c2ca461.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/e1c5942e7b8f4e3688783b6ad39f04cd.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/3d41ccb91db349c3b684656f44e58cb9.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/201912/c948f65d5ab942b2abbf34bf5e141e26.png" />