冷干机的冷媒介质是（）。
A.氟利昂
B.氮气
C.氨
D.冷媒水
参考答案：A
We have various summer camps for your holidays, You can choose ____ based on your own interests.
A．either
B．each
C．one
D．it
脱水输液，累积丢失量应于多少小时内补完( )。
A．0.5～1hB．4～6hC．6～8hD．8～12hE．10～12h
