单项选择题
A.general plans B.operating manual C.builders documentation D.CCS file
The circular steel structure installed around the prope...
单项选择题The circular steel structure installed around the propeller of a towboat is the（）.
A.nozzle B.shroud C.strut D.hood
The bow thruster generally is ineffective at（）.A.over 3...
单项选择题The bow thruster generally is ineffective at（）.
A.over 3 knots headway B.at any speed astern C.at any speed ahead D.over 1 knot sternway
Structural bulkheads on a ship are usually（）.A.continuo...
单项选择题Structural bulkheads on a ship are usually（）.
A.continuous B.watertight C.transverse D.non-watertight
