水泵的比转数又称比速，用符号“（）”表示。单位是r/min。A、n B、ns C、H D、

对原发性胆汁性肝硬化最有诊断价值的免疫学检查是（）。

A.抗线粒体抗体阳性+IgM阳性

B.类风湿因子阳性

C.抗线粒体抗体阳性+IgA阳性

D.抗核抗体阳性

E.抗平滑肌抗体阳性

Achieving a goal takes time. ____ in life comes immediately.

A．Few

B．Much

C．Some

D．Little

简述教育各构成要素在教育活动中的地位及相互联系。

--- I had thought he would be nervous in this speech competition, but he turned out to be calm.

--- He        quite enough preparation for it.

A．should do

B．must do

C．should have done

D．must have done

声卡是负责录音、播音和（）的计算机硬件插卡。

A、采集图象

B、声音合成

C、连接网络

D、显示图象