please help with excel formulas

Required: 1. Express the balance sheets in common-size percents. (Use celis A4 to D17 from the given information to complete this question.) 2. Assuming annual sales have not changed in the last three years, is the change in accounts receivable as a percentage of total assets favorable or unfavorable? 3. Assuming annual sales have not changed in the last three years, is the change in merchandise inventory as a percentage of total assets favorable or unfavorable