—  _______?

— Will you please get me some medicine so that I can have a good sleep? [       ]

A. How are you feeling            

B. What's the matter

C. Is there anything wrong          

D. Can I help you

柱塞泵的（）与柱塞的直径、行程和往复次数等有关，与排出压力无关。

A、扬程

B、效率

C、流量

D、有效功率