A single-phase 15-kVA, 1440/120-volt, 60-Hz distribution transformer is used as a step-down transformer at the load end of a 1440-volt feeder whose series impedance is (1.0 + j2.0) ohms. The equivalent series impedance of the transformer is (1.0 + j2.5) ohms referred to the high-voltage (primary) side. The transformer is delivering rated load at a 0.8 power factor lagging and at a rated secondary voltage. Neglect the transformer exciting current. Using the transformer ratings as base quantities, do the following calculations in per-unit. (Assume the phase angle of the secondary winding voltage is 0°.) (a) Determine the voltage at the transformer primary terminals. (Enter your answer in polar form. Round the magnitude in V to at least the nearest 10 V. Enter the phase angle in degrees.) ? ° V (b) Determine the voltage at the sending end of the feeder. (Enter your answer in polar form. Round the magnitude in V to at least the nearest 10 V. Enter the phase angle in degrees.) ? ° V (c) Determine the real power (in kW) and reactive power (in kvar) delivered to the sending end of the feeder. (Use the generator convention.) PS= kWQS= kvar