Q4: Consider the plant with the transfer function given by Gp(s)=s(s+2)(s+4)1 (a) Design an analog PD controller such that the resulted closed loop system has dominant poles at s1,2=4/2 (b) Discretize the controller obtained in (a) and write down the corresponding difference equation. (c) Write down a programming code to implement the controller using digital computer or microcontroller. (d) Sketch the block diagram of the closed loop digital control system showing AD and DA convertors