$|\overrightarrow{ F }|= ILB \sin \theta$
$=(2)\left(5 \times 10^{-2}\right) \times \frac{3}{4} \times \frac{12}{13}=\frac{9}{130}\,N$
So, $x=9$


$(A)$ In the region $0 < r < R$, the magnetic field is non-zero.
$(B)$ In the region $R < r < 2 R$, the magnetic field is along the common axis.
$(C)$ In the region $R < r < 2 R$, the magnetic field is tangential to the circle of radius $r$, centered on the axis.
$(D)$ In the region $r > 2 R$, the magnetic field is non-zero.