A commercial building is subject to an electricity rate schedule that requires a demand charge of $2.50 per kVA per month. The electrical load of the building consists of (a) a group of ten (10) identical induction motors, (b) a plug load of 200 kW with a power factor of 0.90, and (c) of lighting load of 50 kW with a power factor of 0.80. Each motor has the following nameplate rating: 480 V, 30 A, 20 HP, 1780 rpm, 0.70 power factor at full load. Determine

(a) The efficiency, the number of poles, and the slip factor of each motor

(b) The capacitor (expressed in kVAR and in μF) needed to raise the power factor of the building to 0.90

(c) The annual savings in the power bill for the plant due to the increase in the power factor