Three single-phase two-winding transformers, each rated 25 MVA, \(34.5 / 13.8 \mathrm{kV}\), are connected to form a three-phase \(\Delta-\Delta\) bank. Balanced positive-sequence voltages are applied to the high-voltage terminals, and a balanced, resistive Y load connected to the low-voltage terminals absorbs \(75 \mathrm{MW}\) at \(13.8 \mathrm{kV}\). If one of the single-phase transformers is removed (resulting in an open- \(\Delta\) connection) and the balanced load is simultaneously reduced to \(43.3 \mathrm{MW}\) (57.7\% of the original value), determine

(a) the load voltages \(V_{a n}, V_{b n}\), and \(V_{c n}\);

(b) load currents \(I_{a}, I_{b}\), and \(I_{c}\); and

(c) the MVA supplied by each of the remaining two transformers. Are balanced voltages still applied to the load? Is the open- \(\Delta\) transformer overloaded?