Duck Textiles Inc. produces and sells a decorative pillow for 98 per unit. In the first month of operation, 2,300 units were produced and 1,900 units were sold. Other information for the month includes: Variable manufacturing costs 22 per unit Variable marketing costs 16 per unit Fixed manufacturing costs 15 per unit Administrative expenses, all fixed 21 per unit Ending inventories: Direct materials -0- WIP -0- Finished goods 500 units What is the contribution margin using variable costing?