12.於無線電話機中收到“MAYDAY,MAYDAY,MAYDAY”呼叫時,表示本通信文屬於下列何
種性質?
(A)Distress call
(B)Urgency call
(C)Safety message
(D)General message
答案:登入後查看
統計: A(207), B(2), C(1), D(0), E(0) #646520
統計: A(207), B(2), C(1), D(0), E(0) #646520