DVD光盘为存储容量为4.7GB，是CD-ROM盘的（）倍。
A.12
B.10
C.7
D.5
参考答案：D
They chatted ____ coffee about their experience as volunteers during the charity.
A．over
B．on
C．to
D．with
CFM56-7B发动机低压涡轮间隙控制是通过（）来实现
A.风扇排气
B.低压压气机排气
C.风扇和低压压气机排气
D.高压2级排气
