The figure shows the single-line diagram of a synchronous generator delivering $\mathrm{P}=50 \mathrm{MW}$ of power at unity power factor to an infinite bus.

$I_s$ denotes the stator current phasor. If the field excitation is increased, which one of the following options correctly describes its effect on the stator current, power factor, and load angle of the machine?

An alternator with an internal voltage of $1 \delta_1$ pu and synchronous reactance of 0.4 pu is connected by a transmission line of reactance 0.1 pu to a synchronous motor having synchronous reactance 0.35 pu and internal voltage of $0.85 \delta_2 \mathrm{pu}$. If the real power supplied by the alternator is 0.866 pu , then ( $\delta_1-\delta_2$ ) is $\_\_\_\_$ degrees (Round off to 2 decimal places). (Machines are of non-salient type. Neglect resistances)