A single fitting installed in a pipeline that either blanks off the pipe or allows a full flow passage of a liquid through the pipe is referred to as a（）.

单项选择题A set of interior steps on a ship leading up to a deck from below is known as（）.

A.a companion way
B.tween-decks
C.stairs
D.Any of the above are acceptable

单项选择题A measurement device for inspecting anchor chain is the（）.

A.slide rule
B.go-no-go gauge
C.derrick tape
D.amp probe

单项选择题A design modification of an anchor chain which prevents kinking is the（）.

A.detachable link
B.stud link
C.Kenter link
D.connecting link

单项选择题A deck fitting，used to secure line or wire rope，consisting of a single body with two protruding horns is called a（）.

A.bitt
B.bollard
C.capstan
D.cleat

单项选择题A contra-guide is a type of（）.

A.bow thruster
B.cargo gear
C.steering engine
D.rudder