Magnetic Field on the Axis of a Circular Current Loop

Two parallel wires separated by $2 \mathrm{m}$ carry currents of $3\mathrm{A}$ each in the opposite directions. Find the magnetic induction for the points between the wires at a distance $50 \mathrm{cm}$from each wire.

For a circular coil of radius R and N turns carrying current I; the magnitude of the magnetic field at a point on its axis at a distance $x$ from its centre is given by,
$B=\frac{{\mathrm{\mu }}_{0}I{R}^{2}N}{2{(X^2+R^2)}^{\frac{3}{2}}}$
Show that this reduces to the familiar result for the field at the centre of the coil.

Two concentric circular coils X and Y of radii $16 \mathrm{cm}$ and $10 \mathrm{cm}$, respectively, lie in the same vertical plane containing the north to south direction. Coil X has $20$ turns and carries a current of $16 \mathrm{A}$; coil Y has $25 \mathrm{turns}$ and carries a current of $18 \mathrm{A}$. The sense of the current in X is anticlockwise, and clockwise in Y, for an observer looking at the coils facing west. Give the magnitude and direction of the net magnetic field due to the coils at their centre.