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單項(xiàng)選擇題

In a （） boiler the hot gases from the furnace pass through the tubes while the water is on the outside.

A.water-tube
B.fire-tube
C.exhaust gas
D.None of the above is true

你可能感興趣的試題

單項(xiàng)選擇題

In a （） boiler the water flows through the inside of the tubes while the hot gases pass around the outside.

A.water-tube
B.fire-tube
C.exhaust gas
D.none of the above

單項(xiàng)選擇題

The tube in a boiler should be blinded if found （）.

A.scaled
B.informed
C.leaky
D.deformed

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