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單項選擇題

With ducted air conditioning systems, the modern tendency is to use（）

A.central air conditioning system
B.high velocity system
C.low velocity system
D.single duct system

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單項選擇題

The（） only allows for adjustment of temperature in each room by the occupant manually controlling the air volume admitted.

A.central air condition system
B.high velocity system
C.low velocity system
D.single duct system

單項選擇題

The volute of centrifugal pump also acts as a diffuser converting （）into pressure head.

A.mechanical energy
B.heat energy
C.potential energy
D.kinetic head

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