单项选择题
A FICTIVE LINE DISPLAYED ON THE RADAR SCREEN SEPARATING THE FAIRWAY FOR INBOUND AND OUTBOUND VESSELS SO THAT THEY CAN SAFELY PASS EACH OTHER defines（）.
A.Separated line B.Divided line C.Reference line D.Segregated line
单项选择题 A Doppler speed log indicates speed over ground（）.
单项选择题 A Doppler log in the volume reverberation mode indicates（）.
单项选择题 A Doppler log in the bottom return mode indicates the（）.
