The following table shows the actual demand observed over the last $11$ years:

This exercise contains only parts $b,c,$ and $d.$

b$)$ Using the $3-$year moving average, provide the forecast from periods $4$ through $12($round your responses to one

decimal place$).$

c$)$ Using the $3-$year weighted moving average with weights $0\mathrm{.}20,0\mathrm{.}25,$ and $0\mathrm{.}55,$ using $0\mathrm{.}55$ for the most recent period,

provide the forecast from periods $4$ through $12($round your responses to two decimal places$).$

d$)$ Mean absolute deviation for the forecast developed using the $3-$year moving average is $2\mathrm{.}23$ and for the $3-$year

weighted moving average is $2\mathrm{.}43.$ Based on this information, the better forecast is achieved using the