For each of the transfer functions below:

$G_1(s)=\frac{3}{(s+1)(s+2)}$

$G_2(s)=\frac{3(s+5)}{(s+1)(s-1)}$

$G_3(s)=\frac{3(s-1)}{(s+3)(s+2)}$

$G_4(s)=\frac{3(5s+1)}{6s^2+5s+1}$

$($a$)$ Find the poles and zeros.

$($b$)$ Indicate whether the response to a step input will converge to a stable final value.

$($c$)$ Find the gain and time constants.

$($d$)$ Indicate whether the response to a step input will have overshoot, an inverse response, or neither.