Comparative income statements for 2008 and 2007 follow. 2008 2007 Sales $9, 434,000 $7,862,000 Cost of Sales 7,075,400 5,660,640 Gross Profit $2,358, 600 $2,201, 360 Operating Expenses 1.367, 690 1.365.060 Operating Income $ 990, 910 $ 836,300 Interest Expense 157,500 126,000 Earnings Before Taxs833, 4105 710,300 Income Taxes 400,000 317, 200 Net Income 433,410$ 393, 100 Required: a. Prepare a vertical common-size analysis of this statement for each year, using sales as the base. b. Comment briefly on the changes between the two years, based on the vertical common-size statement