Q$2.$ a$)$ If $T_{AD}=85**{10}^{-9}(85ns)$ Seconds $($Assume PBclk$-$Freq $=40MHz,[2$ Marks$]$

So $($:$,T_{PB}=\frac{1}{PBclk-\text{F}\text{r}\text{e}\text{q}}$