A balanced three-phase transformer bank with the Δ-Y connection depicted in Fig 13137 ia u...

A balanced three-phase transformer bank with the Δ-Y connection depicted in Fig 13137 ia used to setp down line voltages from 4,500 V rms to 900V rms. If the transformer feeds a 120-kVA load, fund:

(a) the turns radio for the transformer,

(b) the line currents at the primary and secondary sides.