[单选题]Navigational and meteorological warnings ,meteorological forecasts and other safety related messages to shipping , including electronic chart correction date is ___.
[单选题]A radio link between a transmitting earth station and a receiving earth station through one station ,which comprises one up-link and down-ling , is called____
[单选题]When receiving a distress alter , the SAR authorities ashore and the ships in the vicinity of the ship in distress will ------- soonest
[单选题]The quality of EGC message is -----affected by the position the ship ,the time of receptiong and climatic conditions
[单选题]When hearing a distress call ,all station shall immediately cease any transmission capable of _____with the distress traffic.