单项选择题
A “figure eight” knot is used to（）.
A.be a stopper B.shorten a line C.join lines of equal size D.keep a line from passing through a sheave
单项选择题 “15 02 41 Semi Double Queen 195 332mm”is a description of（）.
单项选择题 （） is true.
单项选择题 Your vessel is equipped with a fixed CO2 system and a fire main system. In the event of an electrical fire in the engine room what is the correct procedure for fighting the fire?（）
