心肺复苏心脏按压时，按压与放松时间之比应为（） A.70％：30％ B.60％：40

污染切口是指（）

A.腹股沟疝修补术

B.胃大部切除术

C.胆囊切除术

D.阑尾穿孔切除术

E.小肠部分切除术

I decided to go to the library as soon as I ______.

A．finished what I was doing

B．finished what I did

C．would finish what I was doing

D．finish what I did

发电机在正常运行中，增加无功有功也增加。

精神药品分为第一类精神药品和第二类精神药品。

分离数据库