单项选择题
A.velocit in knot B.irection from which it flows C.estimated current D.direction toward which it flows
Several shoals（）reported to exist in the area south-wes...
单项选择题Several shoals（）reported to exist in the area south-west of the Brothers.
A.have B.have been C.has D.has been
A system of cleaning the tanks by washing them with the...
单项选择题A system of cleaning the tanks by washing them with the cargo of crude oil while it is being discharged is known as（）.
A.cow B.lot C.cbt
A vessel emitting harmful substances into the air or sp...
单项选择题A vessel emitting harmful substances into the air or spilling oil into the sea is a（）.
A.polluter B.emitter C.spiller D.oiler
