Please answer this question. A: 180 watts. B: 215 watts. C: 200 watts. D: 30 watts.

The band lineup has constantly been changing. Since Bill Wyman left the band in 1993, we have had only 4 official members in the band. Who are they? A: Mick Jagger, Keith Richards, Bill Wyman and Brian Jones. B: Mick Jagger, Keith Richards, Bill Wyman and Charlie Watts. C: Mick Jagger, Keith Richards, Ronnie Wood and Mick Taylor. D: Mick Jagger, Keith Richards, Charlie Watts and Ronnie Wood.

A power factor(功率因子) of 60% means that 1 Kva(千伏瓦) of power must be supplied for every 600 watts of power actually consumed(消耗), an uneconomical situation.