What is used to prevent twisting of a towing bridle?（）

单项选择题What is the purpose of cant frames in steel vessels? （）

A.To support the overhang of the stern
B.To provide strength to shell plating at the stern
C.To add strength to the deck beams which support the weather decks
D.To support the plating of a cylindrical tank

单项选择题What is the purpose of a striker plate? （）

A.Provides surface for applying force on machinery
B.Provides landing surface for the sounding bob
C.Absorbs machinery vibration
D.Prevents valve stem over-travel

单项选择题What is NOT used as a stern tube bearing，on a large vessel? （）

A.Wooden (lignum vitae) strips
B.Hard rubber
C.Resin bonded composition
D.Bronze bushings

单项选择题What best describes the structure from which Stratford Point Light is shown?（）

A.Brown conical tower with white horizontal band in center of light on black pier
B.Red conical tower on brown cylindrical pier
C.White octagonal house on brown cylindrical pier
D.White conical tower，with brown band midway of height

单项选择题Upon underwater（）by divers，there are no apparent（）on the bottom plates of the said vessel.

A.detection，defects
B.defection，defects
C.defects，defection
D.defects，detection