A.10 minutes every 4 hours
B.half an hour every other hour
C.irregular period of time
D.5 minutes every two hours
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A.in any INMARSAT regions
B.in each NAVTEX area
C.at any distance
D.in Areas A3 and A4
A.navigational / typhoon
B.traffic / meteorological
C.marine / hurricane
D.navigational / meteorological
A.dedicated system
B.MSI broadcasts
C.518KHZ
D.channel 16
A.ship’s movement
B.safety
C.ship’s management
D.hazards
A.by day or at night
B.almost round the clock
C.somewhat and sometime
D.from sunrise and sunset
最新試題
Radio communication（）for many years and helps to save tens of thousands of lives.
As each MSI message will have a unique identity, the printing of messages already received correctly is（）.
Before GMDSS, if the radio officer on board is serious ill,（）.
We consider（）send a helicopter with medical facilities to the distress area.
（）will form the basis for distress alerting and safety calling.
The rescue coordination center may（）on stations which interfere with traffic.
Monitoring is especially important in a highly automated system which is dependent on careful（）procedure and format.
All coast radio stations（）DSC installed for VHF and HF.
Radiotelephony communication or radio telex communication or both will be carried out by terrestrial or satellite means,（）the equipment fitted on ship and the area in which the incident occurs.
International Navtex service means the coordinated broadcast and automatic reception on（）khz of maritime safety information by narrow-band direct-printing telegraphy using English language.