Dybala Corporation produces and sells a single product. Data concerning that product appear below: Per Unlt Percent of Sales 100 % 70 % 30% $130 Selling price Variable expenses Contribution margin 91 The company is currently selling 6,200 units per month. Fixed expenses are $220,000 per month. The marketing manager believes that a $6,700 increase in the monthly advertising budget would result in a 240 unit increase in monthly sales. What should be the overall effect on the company's monthly net operating income of this change? O decrease of $2.,660 O increase of $9,360 O decrease of $6,700 O increase of $2,660