The sprocket teeth on a wildcat are known as the（）.……

单项选择题The ratio of the height of a vessel’s rudder to its width is referred to as the（）.

A.aspect ratio
B.constriction ratio
C.rudder ratio
D.steering ratio

单项选择题The projecting lugs of the rudderpost which furnish support to the rudder are called（）.

A.bases
B.gudgeons
C.pintles
D.rudder lugs

单项选择题The owner or Master of a towing vessel shall ensure that all tests and inspections of gear take place and are logged（）.

A.on each watch，immediately before being relieved
B.before embarking on a voyage of more than 24 hours
C.daily，at 1200 local zone time
D.weekly，before 0000 Sunday

单项选择题The owner or Master of a towing vessel shall ensure that all tests and inspections of gear take place and are logged（）.

A.when a new Master assumes command
B.daily，at 0800 local zone time
C.weekly，before 2400 Saturday
D.immediately after assuming the watch

单项选择题The irregular black line around a charted light such as Race Rock Light indicates that it is （）.

A.unwatched
B.surrounded by riprap
C.a minor light
D.constructed on an artificial island