某离散时间系统的系统框图如图所示，其中x表示输入信号，Y表示输出信号，系统的差分方程可以表示为？<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/f17b1754961a482eb540b5229ed1d3b7.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/0769d057673d4151b1f0b41af2ffe512.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/3538ab9355d34bdb854faaddbd64abd6.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/62652baf39794e328f736a5e1dc4a701.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201904/90ff953c2cb044b8a0662afaf143d417.png" />

C语言程序经过编译、连接后生成的可执行文件的扩展名是 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/c27145d4741c4f0f96beadcf86ba18ab.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/9f40e97bb87546d393b24501e95aae0b.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/c7e1150c6e0d4974ae48ddeb44c71cab.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201903/eb4766c9737948f5b631dd909d2b94e4.png" />

已知系统和初始条件<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/15eb73651c0a4ae094e6de902b6c21ca.png" />求初始状态激励的响应 ( )。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/d016acd038b04b699e76c2354357c3d2.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/7a10be8f1ce74599a610fd0b9b9eb195.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/4621f442538946fdb897b89a1461e1e1.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201902/61b797beffc74a99b91e1934af1372fb.png" />

逻辑函数F(A,B,C)=AB+BC+AC的卡诺图为（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201809/7a8254757f8a4fc6ab82fa93a8e86ebf.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201809/229cbcade3654fb99c66a7c102ec046f.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201809/1c851f1288be499c92d2a7b40607bd1a.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201809/3b385269839a45df9645db71096c2e81.png" />

图示结构C截面弯矩为<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/4f75b4fba9ff4be1b04a5e100c86c65e.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/145877d7a442497f9fe1266fa394ba2e.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/1b6f8295e7bc44b0b8a2bee20e062fc4.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/18776e34a7504dfcbe40fbdf73958b14.png" /> D: 0