and operating expenses into their fixed and variable components. a. Use the percent-of-sales method to prepare a pro forma income statement for next year. b. Use fixed and variable cost data to develop a pro forma income statement for next year. c. Compare and contrast the statements developed in parts a. and b. Which statement probably provides the better estimate of income? Explain why. Data table (For Income Staement, click on the icon here (For Breakdown of Costs and Expenses, click on the icon here a spreadsheet.)