Question $4$:

Using the Routh$-$Hurwitz stability criterion, determine if the feedback control system shown in figure $3\mathrm{.}0$ is stable for the following transfer functions:

a$)G(s)=\frac{100}{s}(s^2+8(s)+24)$

b$)G(s)=\frac{3s+1}{s^2}(300s^2+600(s)+50)$

c$)G(s)=\frac{24}{s}(s+2)(s+4)$

Figure $3\mathrm{.}0$