单项选择题
Any ship fitted with SES can（）and（）through the satellite system when sending a distress alert.
A.enter the system/ contact an RCC B.access to INMARSAT/establish contact with a CES C.have absolutely priority to enter the system/make contact with a CES D.enter the system gradually/wait for rescue
单项选择题 Actually, the date for entry into effect will be 1st February（）.Though the text does not tell us about it.
单项选择题 The GMDSS must combine all various subsystems, because（）.
单项选择题 （）communication are intership VHF radio telephone communication.
