A closed-loop control system with negative unity feedback has a plant with a transfer function
$$
G(s)=\frac{8}{s\left(s^2+6 s+12\right)} .
$$
(a) Determine the closed-loop transfer function $T(s)$. (b) Determine a second-order approximation for $T(s)$ using the method of Section 5.10. (c) Plot the response of $T(s)$ and the second-order approximation to a unit step input and compare the results.