The joint formed when two steel plates are placed end-to-end is called a（）.

单项选择题The inner bottom is the（）.

A.tank top
B.compartment between the tank top and shell of the vessel
C.inner side of the vessel's shell
D.space between two transverse bottom frames

单项选择题The flood stream here is at an average rate of 0.8（）.

A.cables
B.miles
C.kilometers
D.knot

单项选择题The construction portfolio may be included as part of the ship（）.

A.general plans
B.operating manual
C.builders documentation
D.CCS file

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

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