How do I solve the problem in the image? What formulas would I use and what steps would I take to solve the problem?

Problem 15-4 Average Sales Forecast (LG15-3) Suppose a firm has had the following historic sales figures. Year : 2012 2013 2014 2015 2016 Sales $2, 500,000 $3, 750,000 $2, 400, 000 000'090'2$ 000 '009'2$ What would be the forecast for next year's sales using the average approach? Next year's sales