Use the description below for the next THREE questions:

$1.$ What is the forecast for period $16$ using the three$-$period moving average method? $($your answer should be rounded off to the nearest whole number$)$

$2.$ What is the Mean Absolute Deviation $($MAD$)$ for the three$-$period moving$-$average forecast in period $15?$

$3.$ Which forecast is the "best" $($the three$-$period or four$-$period moving average method$)?$ Provide a justification for your answer in terms of measures of forecast accuracy AND bias.