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單項選擇題

However, where immediate action is necessary to ensure safety of the ship, its machinery and crew, it must be taken by the engineer in chargeWhat dose “it” mean in the sentence above?（）

A.safety
B.the ship, its machinery and crew
C.immediate action
D.the engineer in charge

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單項選擇題

There will usually be summaries or daily account tables for heavy oil, diesel oil, lubricating oil, and fresh water, which will be compiled（）

A.at the beginning of every watch
B.at the beginning of the first watch every day
C.at the completion of every watch
D.at noon every day

單項選擇題

According to the principle of two stroke diesel engine, what is the number of its efficient work stroke per revolution?（）

A.1/2
B.1
C.2
D.3