7.6 The readings of open circuit (OC) and short circuit (SC) tests on a single- phase 10 kVA, 450:120 V, 60 Hz transformer are: OC test on the secondary side with primary opened: V= 120 V, I = 4.2 A and W = 80 W SC test on the primary side with the secondary short circuited: V = 9.65 V, I = 22.2A and W = 120 W Determine a. the approximate equivalent circuit. b. the efficiency and voltage regulation when supplying full-load at 0.8 power factor lag. c. the efficiency when supplying half full-load at 0.8 pcwer factor lag.