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單項(xiàng)選擇題

Fire dampers prevent the fire spreading through the process of （）.

A.convection
B.conduction
C.radiation
D.direct contact

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單項(xiàng)選擇題

A fire, occurring in the windings, of an overloaded electrical motor, is considered a （）.

A.class "A" fire
B.class "B" fire
C.class "C" fire
D.class "D" fire

單項(xiàng)選擇題

On a cargo vessel, fire and boat drills must be held within 24 hours of leaving port if the percentage of the crew replaced is more than （）.

A.5%
B.10%
C.25%
D.40%

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