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單項選擇題

To maintain the down stream pressure within defined limits over a range of flow and despite any changes in supply pressure, （） is fitted.

A.a check valve
B.a gate valve
C.a pressure reducing valve
D.a quick closing valve

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單項選擇題

The main objective of the SOLAS Convention is to specify （） for the construction, equipment and operation of ships, compatible their safety.

A.at most references
B.at least references
C.maximum standards
D.minimum standards

單項選擇題

Annex IV of MARPOL 73/78 contains regulations for the prevention of （）.

A.pollution by oil
B.pollution by noxious liquid substances carried in bulk
C.pollution by sewage from ships
D.pollution by garbage from ships

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