单项选择题
why do some stations keep silence?（）
A.Because they are not engaged in the distress traffic
B.they will affect the transmission of the distress traffic
C.The powers of these stations are very weak
D.They are not in charge of search and rescue
相关考题
-
单项选择题
What channel is general communication used?（）
A.any appropriate channel except public communication
B.any appropriate channel except for public communications
C.any appropriate channel besides public communication
D.any appropriate channel beside public communication -
单项选择题
What’s the advantage when using the satellites?（）
A.The message can be directed to the desired location
B.The message can follow the earth’s curvature
C.The quality of message can not be affected by climatic
D.The range of the message extend and the quality of reception is improved -
单项选择题
Any ships 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 absolute priority to enter the system / make contact with a CES
D.enter the system gradually / wait for rescue
