Can somebody please clearly explain step-by-step how to use Excel Data Analysis to answer the below questions. Thank you.

Q2													20 Marks		Sales
															Month	Sales
															1	125
a) Use = .2 to compute the exponential smoothing forecast for the supermarket sales.				5 Marks			2	141
															3	125
b) Use = .3 to compute the exponential smoothing forecast for the supermarket sales.			5 Marks			4	123
															5	126
c) Use = .4 to compute the exponential smoothing forecast for the supermarket sales.				5 Marks			6	145
															7	147
d) Does a smoothing constant of .2, .3 or .4 appear to provide more accurate forecasts based on MSE? Explain.	5 Marks			8	162
Note: show your MSE calculations.												9	155
															10	158
															11	147
															12	159