单项选择题
A.be visible from both sides and from forward and aft
B.indicate NO SMOKING
C.be displayed only while transferring cargo and fast to a dock
D.use black lettering on a white background
单项选择题 A SYSTEM OF CLEANING THE TANKS BY WASHING THEM WITH THE CARGO OF CRUDE OIL WHILE IT IS BEING DISCHARGED is known as（）.
单项选择题 When planning the loading or discharging of a VLCC (100，000 DWT+) what is the most important consideration?（）
单项选择题 In all cases，however，the capacity of segregated ballast tanks shall be（）such that，in any ballast condition at any part of the voyage，including the conditions consisting of lightweight plus segregated ballast only，the ship’s draughts and trim can meet the necessary requirements.