1. For the following unity feedback system Gc(s) is a PID controller and G(s) is G(s)=1/[s(s+1)(s+4)]. a) Draw root locus curve for Kp changes from zero to infinity when K1=0 and Kd=0. b) Obtain the Kp,K1, and Kd values of PID controller by using the 2nd Ziegler Nichols Method. c) Draw the modified root locus curve and step response. Do you have a good step response ? d) How could you improve the performance further ? Show on root locus and step response curves. Want it solved on matlab