单项选择题 A spreader bar is used to（）.

单项选择题 A situation has occurred in which your vessel must be towed. When the towing vessel passes the towing line to you，you should secure the line（）.

单项选择题 A loaded hopper barge with independent tanks has a placard，with alternating red and white quadrants，on each side and end. Which statement concerning this barge is TRUE?（）