Data concerning Curtis Corporation's single product appear below: Selling price Variable expenses Contribution margin Per Unit $ 210.00 160.00 $ 50.00 Percent of Sales 100.0% 76.2% 23.8% $ 210,000 4,500 Fixed expenses are per month are: Current monthly units sales are: Marketing manager proposal: Per unit selling price: Increase monthly advertising budget: Target impact of proposal: Unit sales change $ (13) $ 12,500 1,500 Required: a What is the new contribution margin per unit? b What is the new sales volume? What is the new total contribution margin? d What is the current total contribution margin? What is the change in total contribution margin? f What should be the overall effect on the company's monthly net operating income of this change? C e