Gasson Company is a merchandising firm. Next month, the company expects to sell 800 units. The following data describe the company's revenue and cost structure: Selling price per unit $40 Sales commission 5% Purchase price (cost) per unit $18 Advertising expense $4,000 per month Administrative expense $4,500 per month plus 15% of sales Assume that all activity mentioned in this problem is within the relevant range. What is the expected contribution margin next month? $16,000. $17,600. $11,200. $14,400.