单项选择题 You have berthed in a area with other tank vessels. What signal is displayed by a vessel to indicate it is transferring flammable or combustible liquid cargo?（）.

单项选择题 You must shift a weight from the upper tween deck to the lower hold. This shift will（）.

单项选择题 You will load and carry a bulk cargo of sulphur at ambient temperature. Which statement is true?（）.