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單項(xiàng)選擇題

The flame safeguard control system of a large automatic auxiliary boiler will provide fuel shut off in the case of high （）.

A.water
B.voltage
C.fuel pressure
D.steam pressure

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單項(xiàng)選擇題

The operating water is supplied under the （）of an oil separator.

A.sliding bowl bottom
B.bowl hood
C.bowl
D.filter units

單項(xiàng)選擇題

The （）has a water damp ring.

A.purifier
B.oil/water separator
C.incinerator
D.distiller