公共航空运输飞行分为：（）.
A.正班飞行和非正班飞行
B.国际航班和国内航班
B.正班飞行和国际航班
D.非正班飞行和国内航班
参考答案：A
A: I've just heard that the tickets for the new movie have been sold out! B: Oh, no! ______
A．It doesn't matter.
B．It's not at all interesting.
C．I was looking forward to it.
D．I knew it already.
电子设备抗干扰常用的隔离法是（）。
A、用变压器隔离
B、用光耦隔离
C、用继电器隔离
D、A、B、C三种
