Required information [The following information applies to the questions displayed below. Data for Hermann Corporation are shown below: The following information Per Unit $115 Percent of Sales 100% Selling price Variable expenses Contribution margin 46 40% Fixed expenses are $83,000 per month and the company is selling 2,500 units per month. Required: 1-a. The marketing manager argues that a $8,800 increase in the monthly advertising budget would increase monthly sales by $19,000. Calculate the increase or decrease in net operating income. 1-b. Should the advertising budget be increased