$1\mathrm{.}5$mm wire $($Rw$=1$KOhm and Cw$=200$fF$)$ is used to connect INVx$1$ to a load equivalent to $256$Cinv.

a$)[5$ Pts$]$ Calculate the delay from the input of the INVx$1$ to the load. Use Elmore delay and the $1-$segment PI model.

b$)[5$ Pts$]$ To reduce the delay, we insert two inverters $($each is INVx$4)$ in between the driver $($INVx$1)$ and the load by dividing the

wire into three equal segments. Calculate the delay from the Calculate the delay from the input of the INVx$1$ to the $256$Cinv

load.

c$)[10$ Pts$]$ Suggest different sizes for the two inverters introduced in Part $($b$)$ to reduce the delay further