单项选择题
（）loading,5 drums were found leaking.
A.In B.from C.At D.During
单项选择题 （）refers to the angle between true north and the heading line of the ship.
单项选择题 （）tankers over 100 meters long must not proceed beyond Dongbei buoy.
单项选择题 （）the canal transit, the radar was operating.
