单项选择题
A.mark the position of a lost mooring B.determine your vessel's sideslip underway C.determine your speed through the water D.indicate location of a man overboard
（）the survivors known more of how to cope with cold wat...
单项选择题（）the survivors known more of how to cope with cold water in the sinking of MV Titanic in 1912 countless lives（）.
A.Have／could have been saved B.Have／could have saved C.Had／could has saved D.Had／could have been saved
