Here are the actual tabulated demands for an item for a nine$-$month period $($January through September$).$ Your supervisor wants to test two forecasting methods to see which method was better over this period.$\backslash$table$[[$MONTH$,$ACTUAL$],[$January$,110],[$February$,130],[$March$,150],[$April$,160],[$May$,170],[$June$,180],[$July$,140],[$August$,130],[$September$,140]]$

a$.$ Forecast April through September using a three$-$month moving average.

c$.$ Use MAD to decide which method produced the better forecast over the six$-$month period.

Please provide Excel formulas for solutions.