A three-phase Y- connected transformer bank (single phase) consists of three identical step-up transformers rated at 100MVA, 13.8kV:66.4kV. Each transformer has a series impedance of .0045 + j0.19-ohm referred to its 13.8kV winding. Calculate the following
a. the rated line voltage at the primary side
b. the rated line voltage at the secondary side.
c. the VA ratings on both sides
d. the equivalent impedance as referred to the secondary side