Selling price Variable expenses Contribution margin Per Unit $ 135 81 $ 54 Percent of Sales 100% 60 40% Fixed expenses are $87,000 per month and the company is selling 2,900 units per month 2-a. Refer to the original data. How much will net operating income increase (decrease) per month if the company uses higher-quality components that increase the variable expense by $5 per unit and increase unit sales by 20%. 2-b. Should the higher-quality components be used? Complete this question by entering your answers in the tabs below. Req 2A Reg 2B Refer to the original data. How much will net operating income increase (decrease) per month if the company uses higher- quality components that increase the variable expense by $5 per unit and increase unit sales by 20%. Net operating income increases by