Confirm your calculations in Requirement 3 above by increasing the unit sales in your worksheet by 20% so that the Data area looks like this: 1 Chapter 5: Applying Excel 2 3 Data Unit sales 5 Selling price per unit 6 Variable expenses per unit 7 Fixed expenses 4 8 Net operating income (loss) 12,000 units $ $ $ 280,000 70 per unit 35 per unit (a) What is net operating income? (Negative amount should be indicated by a minus sign.) (b) By what percentage did the net operating income increase? Percentage increase in net operating income %