单项选择题
In Inmarsat-A, “Priority 0” means（）communication.
A.routine B.distress C.urgency D.safety
单项选择题 The maritime access code for the IOR is（）in INMARSAT-A Telex Service.
单项选择题 In Inmarsat-A, “Priority 3” means（）communication.
单项选择题 Who has permit the SES enter the system after successful commissioning?（）
