下列HF设备中哪一部负责数据通讯?()
A、第1部
B、第2部
C、第3部
参考答案:A
Language belongs to each member of the society, to the cleaner () to the professor.
A.as far as
B.the same as
C.as much as
D.as long as
桨尖涡流产生是由于哪种阻力()
A.诱导阻力
B.翼型阻力
C.废阻
D.型阻