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單項選擇題

Copper is often used as an electrical conductor because it （）.

A.has high resistance at low temperatures
B.has a highly polished surface
C.is able to pass current with little opposition
D.holds insulation together well

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單項選擇題

A device which prints out a permanent record of the plant operating conditions is known as the （）.

A.analogger
B.bell logger
C.alarm logger
D.data logger

單項選擇題

Which of the following types of motors is often designed for use in correcting power factor?（）

A.Polyphase
B.Wound-rotor
C.Induction
D.Synchronous