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: 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 8,000 units to 1. 12,000 units. 2. 4,000 units. d. Refer to your answer to part a for total revenues of $32,000. Calculate the firm's operating income (or loss) if unit selling price and variable expenses per unit do not change and total revenues 1. Increase $12,000. 2. Decrease $7,000. \begin{tabular}{|l|l|l|} \hline \multicolumn{2}{|c|}{ Contribution Margin Income Statement } \\ \hline Revenue & & $32,000 \\ \hline Variable expenses: & & \\ \hline Administrative expenses & & \\ \hline Cost of goods sold & & \\ \hline Selling expenses & & \\ \hline & & \\ \hline Total variable expenses & & \\ \hline & & \\ \hline Fixed expenses: & & \\ \hline Administrative expenses & & \\ \hline Cost of goods sold & & \\ \hline Selling expenses & & \\ \hline Total fixed expenses & & \\ \hline Operating income & & $ \\ \hline \hline \end{tabular}