A manufacturing company produces 4 products (AAA, BBB, CCC, and DDD). The previous year's sales and product structure have been illustrated in the Excel file.

1. Please use Excel tools to plot-line chart for each product.
2. Review the sales history of these four products and discuss demand behaviour. Can you see any trends? What about seasonality? Which product has only random sales fluctuations? For your answer, you need to show reason and justification.
3. Determine demand forecast for January 2022 by using the Simple Average Method. Determine demand forecast for January 2022 by using the Moving Average Method (moving average of 6 periods).
4. Determine demand forecast for January 2022 by using the Weighted Moving Average Method. Weights of last 6 months are 30%, 25%, 15%, 15%, 10%, 5% respectively.
5. Determine demand forecast for January 2022 by using the Exponential Smoothing Method. Assume that the Smoothing Factor is 0.2 and you only have sales information for October, November, and December.