Case (i): When Ef is increased by 20% Power factor pf= 0.75 lagging Reactive power drawn by the load = 511.2 MVAR Case (ii): When Ef is decreased by 20% Power factor pf= 1.00 lagging Reactive power drawn by the load = 19.5 MVAR The answers given here are exact values.Textbook answers has an approximat ion of upto 2 decimal places on Xs,Ia,pf.