设<imgwidth="50"height="17"src="http://wljy.whut.edu.cn//uploadfiles/word/lsss002.files/image018.png">,则有( )
①
<imgwidth="35"height="16"src="../uploadfiles/word/lsss002.files/image019.png">
②
<imgwidth="37"height="18"src="../uploadfiles/word/lsss002.files/image020.png">
③
<imgwidth="37"height="19"src="../uploadfiles/word/lsss002.files/image021.png">
④
<imgwidth="38"height="20"src="../uploadfiles/word/lsss002.files/image022.png">