d. Refer to your answer to part a when total revenues were $108,000. 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 $15,000

2. Decrease by $10,000

Prepare a contribution margin format income statement; answer what-if questions Shown here is an income statement in the traditional format for a firm with a sales volume of 18,000 units: $108,000 60,400 $ 47,600 Revenues... Cost of goods sold ($10,000 + $2.80/unit) Gross profit Operating expenses: Selling ($2,200+ $1.00/unit) Administration ($5,000+ $0.40/unit) Operating income 20,200 12,200 $ 15,200 Required: 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 15,000 units to 1. 20,000 units. 2. 10,000 units