A pharmacist has been monitoring sales of a certain over$-$the$-$counter pain reliever. Daily sales during the last $15$ days were

$\backslash$table$[[$Day:$,1,2,3,4,5,6,7,8,9],[$Number$,36,38,43,45,45,46,46,51,51],[$sold:$,10,11,12,13,14,15,,,],[$Day:$,46,54,48,56,58,50,,,],[$Number$,46,,,,,,,,],[$sold:$,,,,,,,,,]]$

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a$.$ Assume the data refer to demand rather than sales. Using trend$-$adjusted exponential smoothing with an initial forecast of $46$ for Day $8,$ an initial trend estimate of $2,$ and $==\mathrm{.}3,$ develop demand forecasts for Days $9$ through $16.$ Then compute the resultant MSE using the error values from Days $8$ through $15.($Round your intermediate period$-$by$-$period forecast and error values to $3$ decimal places. Round your final MSE answer to $3$ decimal places.$)$

MSE