A $3 \phi$, six-pole, $2080 \mathrm{~V}, Y$-connected synchronous machine is operated as a generator. The generator delivers $300 \mathrm{kVA}$ at a power factor of 0.75 lagging. Find the induced voltage, $E_f$, and rotor angle, $\delta$, if the per-phase stator impedance is $\mathbf{Z}_s=0.1+j 8 \Omega$. Note that in this case we are simply including the effects of stator winding resistance.