---Please inform Tom of the exact time of the arrival of the plane.

---________? He will come here tonight.

A．Why bother

B．Why not

C．So what

D．What for

为使稳压阀（气相色谱中）有较好的稳压效果，一般使稳压阀入口气体压力（）。

A.不超过6×10⁵Pa

B.大于6×10⁵Pa

C.不超过3×10⁵Pa

D.大于3×10⁵Pa