Extra Credit Problem H$($z$)=($Y$($z$))/($x$($z$))=($z$)/($z$-0\mathrm{.}5)$ and ROC:$|$z$|>0\mathrm{.}5$

a$)$ x$[$n$]=$u$[$n$].$

b$)$ x$[$n$]=$n$*$u $[$n$].$