Problem 12-21 (Algo) Prepare a contribution margin format income statement; answer what-if questions LO 12-7, 12-8, 12-9 Shown here is an income statement in the traditional format for a firm with a sales volume of 8,000 units. Cost formulas also are shown: Revenues $ 34,800 Cost of goods sold ($5,700 + $2.10/unit) 22,500 Gross profit $ 12,300 Operating expenses: Selling ($1,180 + $0.09/unit) 1,900 Administrative ($3,650 + $0.20/unit) 5,250 Operating income $ 5,150 Required: Prepare an income statement in the contribution margin format. Calculate the contribution margin per unit and the contribution margin ratio. Calculate the firm's operating income (or loss) if the volume changed from 8,000 units to 12,000 units. 4,000 units. Refer to your answer to part a for total revenues of $34,800. Calculate the firms operating income (or loss) if unit selling price and variable expenses per unit do not change and total revenues Increase by $11,000. Decrease by $3,000.