A.any appropriate channel except public communication B.any appropriate channel except for public communications C.any appropriate channel besides public communication D.any appropriate channel beside public communication
A.between ship stations and shore-based communication networks B.concern the management and operation of ships C.may have an impact of the safety on ships D.all of A, B, C
A.The message can be directed to the desired location B.The message can follow the earth‟s curvature C.The quality of message can not be affected by climatic D.the range of the message extend and the quality of reception is improved