Need help figuring out a$-$c with the alpha as $0\mathrm{.}50$ and and a week $1$ initial forecast of $21\mathrm{.}0$ are $($round your responses to two decimal$$ places$)$:Sales of tablet computers at Marika Gonzalez's electronics store in Washington, D$.$C$.,$ over the past $10$ weeks are shown in the table below:

$\backslash$table$[[$Week$,1,2,3,4,5,6,7,8,9,10],[$Demand$,21,20,29,37,24,30,36,20,25,28]]$

$\backslash$table$[[$Week$,1,2,3,4,5,6,7,8,9,10],[$Demand$,21,20,29,37,24,30,36,20,25,28],[$Forecast$,21\mathrm{.}0,,,,,,,,,$