① <imgwidth="42"height="24"v:shapes="_x0000_i2165"src="http://wljy.whut.edu.cn:80/uploadfiles/word/mndzjs.files/image004.png">,输入电阻小,输出电阻大
② <imgwidth="42"height="24"v:shapes="_x0000_i2166"src="http://wljy.whut.edu.cn:80/uploadfiles/word/mndzjs.files/image004.png">且<imgwidth="42"height="24"v:shapes="_x0000_i2167"src="http://wljy.whut.edu.cn:80/uploadfiles/word/mndzjs.files/image006.png">,输入电阻大,输出电阻小
③ <imgwidth="42"height="24"v:shapes="_x0000_i2168"src="http://wljy.whut.edu.cn:80/uploadfiles/word/mndzjs.files/image004.png">且<imgwidth="42"height="24"v:shapes="_x0000_i2169"src="http://wljy.whut.edu.cn:80/uploadfiles/word/mndzjs.files/image006.png">,输入电阻大,输出电阻小