Shown here is an income statement in the traditional format for a firm with a sales volume of 19,500 units: Revenues. Cost of goods sold ($10,500 + $2.80/unit) Gross profit Operating expenses: Selling ($2,400 + $0.80/unit) Administrative ($4,600 + $0.50/unit) Operating income Required: $ 156,000 65,100 $ 90,900 18,000 14,350 $ 58,550 a. Prepare an income statement in the contribution margin format. b. Calculate the contribution margin per unit and the contribution margin ratio. c. Calculate the firm's operating income (or loss) if the volume changed from 19,500 units to 1. 24,500 units. 2. 11,500 units. d. Refer to your answer to part a when total revenues were $156,000. Calculate the firm's operating income (or loss) if unit selling price and variable expense per unit do not change and total revenues 1. Increase by $13,000. 2. Decrease by $7,500. Complete this question by entering your answers in the tabs below. Required A Required B Required C1 Required C2 Required D1 Required D2 Prepare an income statement in the contribution margin format.