For the following transfer functions determine the zero$-$pole diagrams and discuss circuit stability.

a$)G(s)=\frac{s(s+2)}{(s+3{)}^2(s^2+6s+34)}$

b$)G(s)=\frac{s^2(s+5)}{(s+2)(s^2+2s+17)}$

c$)G(s)=\frac{(s-2)}{(2s+3)(s^2+9)}$

d$)G(s)=\frac{5s(s+1)}{(s^2+4{)}^2(s^2+6s+9)}$