Generator conneced to buses 1 and 2 have their subtransient reactances includen in Z bus If prefauit current is neglected, find the subtransient current in per-unit the fault for a thre-phase fault on bus 4 . Assum the voltage at the fault is 1.0 per-unit before the fault occurs Find alos the per unit current from Generatoe 2, whose subtransient reactanceis is 0.2 per unit