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單項(xiàng)選擇題

For pumping the bilges,a 54 foot long “T-Boat”,which is not a ferry,but is certificated to carry 30 passengers,must be fitted with at least().

A.one fixed power pump and one portable hand pump
B.one fixed hand pump and one portable hand pump
C.two portable hand pumps
D.either "A" or "B"

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