A 6-pole, 3-phase, 50 Hz synchronous motor is supplied from 6.6 kV busbars. Its opencircuit voltage is 3.3 kV/phase. The per phase resistance and synchronous reactance are 0.6 Ω and 4.8 Ω respectively. Calculate the current, power factor and torque developed, when the excitation emf lags the busbar voltage by 15°, 25°, and 35° (elect).