单项选择题
A.instructed in the use of portable fire extinguishers
B.shown a video demonstrating lifeboat launching
C.instructed in the use of life jackets
D.not required to attend the boat drill
单项选择题 During a training exercise a submarine indicating that a torpedo has been fired will send up smoke from a float. The smoke’s color will be（）.
单项选择题 During a fire drill on a ship，what action is required?（）
单项选择题 Due to the hazards involved with Halon extinguishers on a ship，the size II extinguisher may only be used（）.