I'm having trouble solving this. what formula is required to solve this?

The management team of Marigold Industries was evaluating its performance for the first half of the year. Production and sales of its fans were on budget at 2,900 units to date, with the following income statement reflecting its income for the first half of the year. (b) Assume instead that the customer requests 100 units in the special order and offers $39 per unit. Marigold management still believes there will be enough capacity to take on the special order. This time, however, variable selling costs will be incurred because the customer is working through a sales representative. How much better or worse off will Marigold Industries be if it accepts this special order? Marigold Industries would be by $ by accepting this order. eTextbook and Media Orders for the second half of the year were coming in slower than what the company had been expecting. When a new customer called and requested a special discount, the sales team listened. (a) Assume the customer requests 210 units in the special order and offers $46 per unit. Since the customer came directly to the company, no variable selling cost will be incurred. How much better or worse off will Marigold Industries be if it accepts this special order, assuming it has enough idle capacity for the order? (c). Assume instead the customer requests 150 units and both a discounted price of $49 per unit and a customized version of the fan. In order to make the customized version, Marigold will need to purchase a special piece of equipment for $3,775, but it will not incur any variable selling costs for this order. How much better or worse off will the company be if it uses its available capacity and accepts this special order? Marigold Industries would be by $ by accepting this order. Marigold Industries would be by $ by accepting this order