A 100-KVA, 2500/125-V, 50-Hz, step-down transformer has the following parameters: RH= 1.5 ohm ,XH= 2.8 ohm , RL=15 m omh XL = 2.m ohm, ,RcH=3 k ohm, XmH = 5k ohm. The transformer delivers 85% of the rated load at a terminal voltage of 110V and a power factor of 0.866 lagging. A draw equivalent circuit Determine b. The core loss c. the copper loss d. the efficiency of the transformer