A 10 kVA, 2500/250 V, 50 Hz distribution transformer. If the rated load is withdrawn at 0.8 power factor lagging. Note that the values of the constants are in ohm referred to the low voltage side. At which power factor the voltage regulation will be zero? 0-118519 jo-23888 -ell 755-715 j693.878 Possible answers: A) zero leading B) 0.55 lagging C) 0.5 leading D) 0.63 leading E) 0.45 leading F) None.