单项选择题
On a twin-screw，twin-rudder vessel，the most effective way to turn in your own water，with no way on，is to put（）.
A.one engine ahead and one engine astern，with full rudder B.one engine ahead and one engine astern，with rudders amidships C.both engines ahead，with full rudder D.both engines astern，with full rudder
单项选择题 On a single-screw vessel the stern frame（）.
单项选择题 In selecting a tug for moving a vessel，consideration should be given to its（）.
单项选择题 In order to reduce your wake in a narrow channel you should（）.
