The following contribution format income statement is obtained from Machos Nachos Ltd. All questions concern situations that are within the relevant range. Sales (3,000 units) $ 180,000 Variable expenses 126,000 Contribution margin 54,000 Fixed expenses 52,200 Net operating income $ 1,800 Required: a. If the selling price increases by $4 per unit and the sales volume decreases by 300 units, what would be the estimated net operating income? b. If the variable cost per unit increases by $6, spending on advertising increases by $3,000, and unit sales increase by 1,800 units, what would be the estimated net operating income