单项选择题
How（）the cargo at loading port?
A.about B.in C.with D.from
单项选择题 Channel 13 (156.65 MHz)，the designated bridge-to-bridge channel，may NOT be used to（）.
单项选择题 All VHF marine band radios operate in the simplex mode，which means that（）.
单项选择题 A mark or place at which a vessel comes under obligatory entry，transit，or escort procedure is know as（）.
