According to Question

Two small bar magnet is $r=0.1 \mathrm{m}$ apart from their centre

Magnetic moment$=M_1=M_2=5 {\mathrm{Am}}^2$

Now The relation of force$\left(F\right)$ and magnetic moment $\left(M\right)$ in two small bar magnet

$\mathit{\text{F}}=\frac{{\mu }_{\mathit{0}}}{\mathit{4}\pi }\mathit{·}\frac{\mathit{6}{\mathit{\text{M}}}_{\mathit{1}}{\mathit{\text{M}}}_{\mathit{2}}}{{\mathit{\text{ r }}}^{\mathit{4}}}$

Put the all known values in the above relation
$F=\frac{10^{-7}\times 6\times 5\times 5}{{\left(\text{0.1}\right)}^4}$

$F=\text{0.15 N}$