Write a program in MATLAB for a unity-feedback system with [G(s)=frac{K(s+3)}{left(s^{2}+5 s+80 ight)left(s^{2}+4 s+20 ight)}] (a) plot

Write a program in MATLAB for a unity-feedback system with

\[G(s)=\frac{K(s+3)}{\left(s^{2}+5 s+80\right)\left(s^{2}+4 s+20\right)}\]

(a) plot the Nyquist diagram

(b) display the real-axis crossing value and frequency.