Which system is often used to provide accurate vessel position information to the GMDSS equipment？
A. COSPAS-SARSAT
B. GPS
C. EPIRB
D. INMSRSAT-F
What is the basic concept of GMDSS？
A. Search and rescue authorities shore can be alerted to a distress situation
B. shipping in the immediate vicinity of a ship in distress will be rapidly alerted
C. Shore-side authorities and vessels can assist in a coordinated SAR operation with minimum delay
D. All of these
下列所述的哪一个是无连接的传输层协议()。
A. tcp
B. udp
C. ip
D. spx
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