For each of the transfer functions shown below:

i$.$ find the locations of the poles and zeros

ii$.$ plot them on the s$-$plane

iii. Write an expression for the general form of the step response without solving for the inverse Laplace transform.

iv$.$ State the nature of each response

a$.T(s)=\frac{20}{s^2+6s+144}$

b$.T(s)=\frac{s+2}{s^2+9}$

c$.T(s)=\frac{(s+5)}{(s+10{)}^2}$