$1)$ Write a MATLAB script to generate and plot the sequence f$($n$)=$ A$($a$)^($n$),$ with A $=10$ and a $=-0\mathrm{.}9$ for $-10<=$ n $<=10.2)$ Write a MATLAB script to generate and plot the sequence g$($n$)=$ A$($a$)^($n$)$ u$($n$)$ with A $=10$ and a $=-0\mathrm{.}9$ for $-10<=$ n $<=20$