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
On-scene communications will normally take place between（）.
As each MSI message will have a unique identity, the printing of messages already received correctly is（）.
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.
The quality of EGC messages is（）affected by the position of the ship, the time of reception and climatic conditions.
Distress traffic is the communication（）between the station in distress and the ships, aircraft, coast radio stations, coast earth stations and rescue centers participating in the rescue work.
COSPAS-SARSAT is intended to be used for（）.
SafetyNet is an international service for the broadcast and automatic reception of MSI by means of direct-printing through（）system.
Ship-to-ship distress alerting should be conducted by（）.
All coast radio stations（）DSC installed for VHF and HF.
Stations in the United States of America are grouped by states arranged in the alphabetical order of their（）.