Hi Can you please explain how to solve this question?

Fletcher Corporation prepared the following income statement for the fourth quarter in 2018.

Sales revenue (30,000 units) $930,000

Less: Costs of goods sold 586,600

Gross margin 343,400

Less: Selling & administrative expenses 184,600

Net income $158,800

Fletcher's annual fixed manufacturing expenses, incurred uniformly each quarter, amount to $834,400; it also pays a sales commission of $2 per unit to its sales personnel.

how do you make a contribution margin income statement for the fourth quarter in 2018?