单项选择题

In a three-phase circuit, the phase voltages are （）

A.120°apart
B.160°apart
C.180°apart
D.360°apart

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单项选择题

Which of the following statements is true concerning simple parallel resistance circuits?（）

A.The total current flow equals the sum of the individual currents
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C.The total resistance equals the sum of the individual resistance
D.The total voltage equals the sum of the individual voltages across each resistance