Dollar Company incurred the following costs while producing 450 units: direct materials, $8 per unit, direct labor, $20 per unit, variable manufacturing overhead, $18 per unit, total fixed manufacturing overhead costs, $6,750, variable selling and administrative costs, $12 per unit, total fixed selling and administrative costs, $4,050. There are no beginning inventories. What is the operating income using variable costing if 410 units are sold for $130 each? A. $19,320 B. $18,720 C. $23,640 D. $29,520