$8-21$ Three $15$ resistors $(R)$ and three $8$ reactors $(x)$ are connected in different ways across a $530V,3-$phase line. Without drawing a phasor diagram, calculate the line current for each of the following connections:

a$.R$ and $x$ in series, connected in wye

b$.R$ and $x$ in parallel, connected in delta

c$.R$ connected in delta and $x$ connected in wye