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單項(xiàng)選擇題

What type of stern tube bearing has the least friction（）.

A.Oil-lubricated bearings
B.Lignum vitae
C.Hard rubber
D.Bronze bushings

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What is a cofferdam（）.

A.Tube fitted to an ullage hole
B.Area the product is loaded into
C.Void or empty space separating two tanks
D.Opening in the deck used for cleaning a tank

單項(xiàng)選擇題

What can cause a lack of oxygen in a chain locker（）．

A.Absorption
B.Osmosis
C.Evaporation
D.Oxidation