$($a$)$ For $=0\mathrm{.}1$ to $100ra\frac{d}{sec},$ sketch the phase of the minimum$-$phase system

$G(s)=\frac{s+1}{s+10}{|}_s||=jw$

$1$

and the nonminimum$-$phase system

$G(s)=-\frac{s-1}{s+10}{|}_s||=jw$

$,$ noting that $\frac{?}{{?}_{jw-1}}$ decreases with $$ rather than increasing.

$($b$)$ Check the stability of the systems in $($a$)$ using the Nyquist criterion on $KG(s).$ Determine the range of $K$ for which the closed$-$loop system is stable, and check your results qualitatively by using a rough root$-$locus sketch.