(1.5 分)
Radar surveillance systems .
A.may provide all ships of their technical conditions B.should be installed with VHF C.shall be correctly interpreted D.is intended to smooth and control the flow of traffic to and from the harbor正确答案D
(1.5 分)
Radar surveillance systems .
A.may provide all ships of their technical conditions B.should be installed with VHF C.shall be correctly interpreted D.is intended to smooth and control the flow of traffic to and from the harbor正确答案D
