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單項選擇題

In order to prevent galvanic corrosion，an aluminum boat must be insulated from the davits and gripes. Which of the following is acceptable as an insulator?（）

A.Hard rubber
B.Canvas
C.Leather
D.Sponge rubber

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單項選擇題

In battery charging rooms，ventilation should be provided（）.

A.at the lowest point
B.near the batteries
C.at the highest point
D.only when charging is in progress

單項選擇題

If passengers are on board when an abandon ship drill is carried out，they should（）.

A.take part
B.watch
C.go to their quarters
D.stay out of the way and do what they want

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