A 50-KVA, 13,800/208 V -Y distribution transformer has an equivalent phase impedance 114.2+j800 ohm referred to the high voltage side. Take the rated voltage as the base voltage and the rated VA as the based voltampere value. (Neglect the exticiation branch of the transformer)
(1) Calculate the phase impedance of the transformer in per unit
(2) Calculate this transformer's voltage regulation at full load and 0.8 PF lagging, using the per-unit system.