$a_{B}=g\left[\sin 45-\mu_{B} \cos 45\right]=\frac{7}{\sqrt{2}}$

$a_{A B}=a_{A}-a_{B}=g\left(\mu_{B}-\mu_{A}\right) \cos 45=\frac{1}{\sqrt{2}}$

$s_{A B}=\sqrt{2}$

Now $s_{\mathrm{AB}}=\frac{1}{2} a_{\mathrm{AB}} \mathrm{t}^{2} \Rightarrow \sqrt{2}=\frac{1}{2} \times \frac{1}{\sqrt{2}} \mathrm{t}^{2}$

$\Rightarrow \quad t=2 \mathrm{sec}$

Again $s_{A}=\frac{1}{2} a_{A} t^{2}=\frac{1}{2}\left(\frac{8}{\sqrt{2}}\right) 4$

$\Rightarrow \quad s_{A}=8 \sqrt{2} \mathrm{m}$