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單項(xiàng)選擇題

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（）.

A.blind flange
B.pivot coupling
C.quick-release coupling
D.spectacle flange

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單項(xiàng)選擇題

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

單項(xiàng)選擇題

A measurement device for inspecting anchor chain is the（）.

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