Data concerning Lemelin Corporation's single product appear below: Percent of Sales 100% 50% Per Unit $ 230 115 Selling price Variable expenses Contribution margin $ 115 50% The company is currently selling 7,000 units per month. Fixed expenses are $581,000 per month. The marketing manager believes that an $11,000 increase in the monthly advertising budget would result in a 100 unit increase in monthly sales. What should be the overall effect on the company's monthly net operating income of this change? Multiple Choice decrease of $11,000 increase of $11,500 decrease of $500 increase of $500