—Shall we have a drink when you finish your talk?

—      .   [ ]

A. No,you can't

B. All right

C. You're welcome

D. You needn't do that

人员需进入气体保护房间前，须将气体灭火转台转为（）位，离开时打回（）位。

A.手动

B.启动

C.自动

D.停止