The equivalent parameters of a 110KVA, 2200V/110V transformer, are R=0.222, R2=0.5m2, X1=2N, X,=5m2, R=5494.52, and Xm=10992. Using the approximate equivalent circuit referred to the primary side, when the transformer is operating at 80% full load with unity power factor determines: 1. Voltage regulation. 2. The transformer power loss. 3. Efficiency.