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單項(xiàng)選擇題

Each ship having an inert gas system must have a portable instruments to measure concentrations of hydrocarbon vapor in inert atmospheres and also to measure（）.

A.nitrogen
B.oxygen
C.carbon dioxide
D.water vapor

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單項(xiàng)選擇題

Each inert gas system must be designed to supply the cargo tanks with a gas，or mixture of gasses，that has an oxygen content by volume of（）.

A.5% or less
B.10% or less
C.15% or less
D.20% or less

單項(xiàng)選擇題

Compared to the amount of concentrated foam liquid used，the amount of low expansion mechanical foam produced is（）.

A.97 times greater
B.94 times greater
C.10 times greater
D.2 times greater

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