图7-51所示电路中，ii=10sinωV，二极管VD2因损坏而断开，这时输出电压的波形和输出电压的平均值为（）。
A.
B.
C.
D.
参考答案：C
— Can Li Ping help me with my English?
— I regret to tell you her English is ____ yours.
A．as good as
B．no better than
C．no more than
D．as much as
简述柴油机活塞组的作用是什么？
