Three single-phase two-winding transformers, each rated 25 M V A , 38.1 / 3.81 k V 25

Three single-phase two-winding transformers, each rated $25MVA,38.1/3.81kV$, are connected to form a three-phase $Y-\Delta$ bank with a balanced Y-connected resistive load of $0.6\Omega$ per phase on the low-voltage side. By choosing a base of 75 MVA (three phase) and $66kV$ (line-to-line) for the high voltage side of the transformer bank, specify the base quantities for the low-voltage side. Determine the per-unit resistance of the load on the base for the low-voltage side. Then determine the load resistance $R_L$ in ohms referred to the high-voltage side and the per-unit value of this load resistance on the chosen base.