Every ship, while at sea,its MF radio installation shall maintain a continuous watch on the distress and safety DSC frequency ____kHz.( )
A.2,187.5 kHz B.8,414.5 kHz C.4,207.5 kHz D.6,312 kHz正确答案A
Every ship, while at sea,its MF radio installation shall maintain a continuous watch on the distress and safety DSC frequency ____kHz.( )
A.2,187.5 kHz B.8,414.5 kHz C.4,207.5 kHz D.6,312 kHz正确答案A