Required information (The following information applies to the questions displayed below.) Data for Hermann Corporation are shown below: Selling price Variable expenses Contribution margin Percent Per Unit of Sales $ 60 1008 39 65 $ 21 354 Fixed expenses are $72,000 per month and the company is selling 4,200 units per month Required: 1-a. How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $9,600, the monthly sales volume increases by 100 units, and the total monthly sales increase by $6,000? 1-6. Should the advertising budget be increased? Complete this question by entering your answers in the tabs below. Reg 1 Reg 1B How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $9,600, the monthly sales volume increases by 100 units, and the total monthly sales increase by $6,000? (Do not round Intermediate calculations Nel operating income by