a. Complete the working paper by computing the financial ratios for 20X5 using Excel. Note: you will lose 20 points if you do not use Excel. To earn maximum points, you will need to use at least two tabs on an Excel spreadsheet. Set up the account balances for each year on the first tab and name the tab "account balances" (include all the accounts from the financial statements that you will need to calculate your ratios). Perform the calculations on the second tab named "workpaper" by linking to the accounts from the account balances tab. Your results on the workpaper tab should look similar to the presentation below. You are just adding the calculations for 12/31/X5. The results for 12/31/X5 should be formatted to look similar to what has already been calculated for 12/31/X4 (see below). For example, the current ratio and times interest earned are expressed as numerical results carried out to one decimal place, while return on total assets and return on net worth are expressed as percentages carried out to one decimal place. b. After completing part (a), review the ratios and identify financial statement accounts that should be investigated because the related ratios are not comparable to prior-year ratios, industry averages, or your knowledge of the company. You can do this a third tab or below your workpaper information. c. For each account identified in part (b), list potential reasons for the unexpected account balances and related ratios. A partially completed analytical ratios working paper for Keystone Computers & Networks, Inc., is presented below. KEYSTONE COMPUTERS & NETWORKS, INC. Prepared by WL Analytical Review Ratios Reviewed by For the Period Ended December 31, 20X5 Ending Ending Ratio 12/31/X5 12/31/X4 Industry Current ratio 1.2 1.3 Days' sales in accounts receivable, computed with average 33.2 37.0 accounts receivable Allowance for doubtful accounts/accounts receivable 1.1% Bad debt expenseet sales 0.2% Total liabilitieset worth 2.7 2.9 Return on total assets 8.3% 9.0% Return on net worth 30.5% 29.0% Return on net sales 1.0% 2.3% Gross profitet sales 23.2% 24.0% Selling, operating, and administrative expenseet sales 21.4% 23.9% Times interest earned 4.1 5.5