There is a system using a P controller with feedback control loop. The process transfer function is Gp(s)=(0.25s+1)0.4 and disturbance transfer function is Gd(s)=(0.25s+1)e4s. The transfer function of the thermocouple and pneumatic valve used in the system are GS(s)=(0.5s+1)16/100mA/C and Gv(s)=(s+1)16mA500kcal/min, respectively. The proportional band value that makes the system continuously oscillating is found as 18% and the response given in the figure is obtained by using this proportional band value. a) Find the optimum P controller parameters to control this system. b) While the tank temperature is kept at set value at 80C, if there is a 50 unit step change in the system disturbance, find the change in T temperature and show on the graph (Use Mathcad program). c) How much off set value is displayed in the system