“I hear Johnson was badly injured in the accident.” “_______ let’s go and see him.”

A．What’s more

B．If so

C．Where possible

D．When necessary

蒸馏法测定水分时常用的有机溶剂是（）。

A、甲苯、二甲苯

B、乙醚、石油醚

C、氯仿、乙醇

D、四氯化碳、乙醚