How do i start of with this question. really dont know what to do

Required information [The following information applies to the questions displayed below] Data for Hermann Corporation are shown below: Percent Of Per Unit Sales Selling price $ 80 100% Variable expenses 44 55 Contribution margin 5 36 45% [ Fixed expenses are $76,000 per month and the company is selling 2,500 units per month. \\ 2-a. Refer to the original data. How much will net operating income increase (decrease) per month if the company uses higherquality components that increase the variable expense by $4 per unit and increase unit sales by 20%. 2-b. Should the higherquality components be used? Complete this question by entering your answers in the tabs below. 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 $4 per unit and increase unit sales by 20%