do in excel please

15. Thorpe Mountain Mining Company's coal reserves are being depleted, so its sales are falling. Also, environmental costs increase each year, so its costs are rising. As a result, the company's earnings and dividends are declining at the constant rate of 4% per year. If the most recent dividend per share was $3 and the required rate of return on the stock is 11%, what is the value of Thorpe Mountain's stock