Sales (In Thousands) of the New Thorton Model 506 Convection

Essay

Sales (in thousands) of the new Thorton Model 506 convection oven over the eight-week period since its introduction have been as follows: ​
a.
Which exponential smoothing model provides better forecasts, one using α = .6 or α = .2? Compare them using mean squared error.
b.
Using the two forecast models in part (a), what are the forecasts for week 9?