Consider a linear and time$-$invariant $($LTI$)$ system with an input x$($t$)$ and a

corresponding output y$($t$)$ given by

$()=()$

$()=[1222]()$

where u$($t$)$ is the unit$-$step.

What is the impulse response h$($t$)$ of the system?

$($A$)()=4()$

$($B$)()=42()$

$($C$)()=42()$

$($D$)()=4$ cos$(2)()$

$($E$)()=4$ sin$(2)()$

$($F$)()=4$ cos$(2)()$

$($G$)()=4$ sin$(2)()$