Figure P7.20 shows a system defined by a transfer function. Use MATLAB to determine the characteristic roots of the system. Describe the nature of the system's transient response to a unit-step input, and consider issues such as the time to reach a steady-state response, and whether or not the transient response exhibits oscillations. Verify your answer with a numerical simulation using MATLAB or Simulink. Lu 800 2s3+ 24s2+ 144s +640 G(s) Figure P7.20 Figure P7.20 shows a system defined by a transfer function. Use MATLAB to determine the characteristic roots of the system. Describe the nature of the system's transient response to a unit-step input, and consider issues such as the time to reach a steady-state response, and whether or not the transient response exhibits oscillations. Verify your answer with a numerical simulation using MATLAB or Simulink. Lu 800 2s3+ 24s2+ 144s +640 G(s) Figure P7.20