a$.$ Calculate the manager$$s forecast error for each month. Answer what is the error of May?

b$.$ What is the mean error $($ME$)?$

c$.$ What is the mean squared error $($MSE$)?$

d$.$ What is the mean absolute deviation $($MAD$)?$

e$.$ What is the tracking signal for these five months of forecasting?

f$.$ If the manager had used a $3-$month moving average instead of her technique, what would have been her forecast for July?

g$.$ If the manager had used simple exponential smoothing with $\backslash$alpha $=0\mathrm{.}2$ instead of her technique, what would the forecast for August be$,$ assuming that simple exponential smoothing had produced a perfectly accurate forecast in March?