16.3 Consider the cascade control system in Fig. E16.3. Use IMC tuning rules for both the master and slave controllers. Design K2 first, and then use that value to design G₁₁ (PI controller). The higher-order transfer function can be approximated first by a FOPTD model using a step test. Plot closed-loop responses for different values of the IMC closed-loop time constant for both outer loop and inner loop for a set point change.