单项选择题
Class C EPIRBs are（）.
A.manually activated and operate on maritime (VHF) channels B.automatically activated and operate on maritime (VHF) channels C.manually operated and detected by satellite D.automatically operated and detected by satellite
单项选择题 Class A EPIRBs are required on（）.
单项选择题 CATEGORY A EPIRB’s transmit on frequencies that are monitored by（）.
单项选择题 All self-propelled vessels on an international voyage must be equipped with how many Emergency Position Indicating Radiobeacons (EPIRB)（）?
