Navigate to the Requirement 3 tab of the Excel workbook to complete requirements 3a. through 3c. Assume the sales mix percentages (as shown in rows 3 and 21) hold constant. Using Goal Seek, calculate the total unit sales required to break even. (Hint: Instruct Goal Seek to obtain a net operating income of $0, as shown in cell Q31, by changing the unit sales in cell Q14.) What are the dollar sales required to break even? What was the companys margin of safety last year? Navigate to the Requirement 4 tab of the Excel workbook to complete requirements 4a. through 4d. Assume the sales mix holds constant and the company plans to increase the selling prices of all products by 5%. (Hint: Focus on cell Q16 to input this projection.) Using Goal Seek, calculate the total unit sales required to break even. Is your answer greater than, less than, or equal to the answer you obtained in requirement 3a? How is the amount in cell B23 calculated? Why does the contribution margin ratio shown in cell R29 differ from the corresponding percentage from last year, as shown in cell R9? Should the company increase its selling prices by 5% this year