Complete the following. $($a$)$ Calculate the transfer function X s$$ F s$$ in terms of the feedback parameter K$.($b$)$ For the case where K $0$ and the input, f$($t$),$ is a unit delta function, $($t$),$ calculate x$($t$)$ using Laplace transforms. $($c$)$ Calculate the value of K that is required for the system to be critically damped $($ $1)$