Problem $8(8$ pts$.)$: For each of the systems described by the transfer functions below, determine the poles and zeros, draw the zeros$-$poles diagram in s$-$plane, and discuss the system stability based on the zeros$-$poles plot. $($Note: you need to justify the stability case$)$

a$)G_1(s)=\frac{s-2}{(s+4)(s^2+6s+10)}$

b$)G_2(s)=\frac{(s+3)}{s(s+2{)}^2(s^2+16)}$