With a （） load the voltage and current are in phase.

The star-delta starter is an effective method of （） voltage starting of a motor.

A.increased
B.reduced
C.unchanged
D.None of the above

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The （）, cage rotor induction motor is the first choice marine motor in most modern ships because of its electrical and mechanical simplicity.

A.single phase
B.two phase
C.three phase
D.four phase

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