某复信号<img src="https://static.zxtiku.com/wangke/imgs/topic/8d5c8d53241dfc03165719bb0e442541.png"/>的频谱如题16图所示，试画出以抽样角频率<img src="https://static.zxtiku.com/wangke/imgs/topic/b3452566870d1a78c424629c34518b71.png"/> 抽样后信号的频谱。( )<img src="https://static.zxtiku.com/wangke/imgs/topic/3cd29b0587374fe58a8871adca7afe5d.jpg"/>