TB Problem Qu. 5-239 (Algo) Shelhorse Corporation produces and... Shelhorse Corporation produces and sells a single product. Data concerning that product appear below: Selling price Variable expenses Contribution margin Percent of Per Unit Sales $ 170 68 $ 102 100% 40% 60% Fixed expenses are $346,000 per month. The company is currently selling 4,100 units per month. Required: The marketing manager believes that a $15,000 increase in the monthly advertising budget would result in a 150 unit increase in monthly sales. What should be the overall effect on the company's monthly net operating income of this change? Change in net operating income