Please finish the following questions using Excel with appropriate formulas;

Q2. Forecasting

ABC Company is creating the production plan for the coming month. The company has collected the following data on the average marketing demand during the past 21 months.

Month	Demand
1	60
2	65
3	67
4	58
5	59
6	56
7	65
8	65
9	69
10	60
11	70
12	71
13	64
14	75
15	70
16	72
17	65
18	77
19	62
20	59

1. Using a three-month moving average, forecast demand for month 21.
2. Using a three-month weighted average with the most recent month weighted 0.55, the next most recent month weighted 0.35, and the third month weighted 0.1, forecast the demand for month 21.
3. Compute an exponentially smoothed forecasting using = 0.32 and forecast the demand 21.
4. Compare the forecast in (a), (b), and (c) using MAD. Indicate the most accurate forecasting method.
5. Compute the tracking signal for the most accurate method (based on MAD value), and construct a control chart. Comment on the forecasting result.