Diggs Company incurred the following costs while producing 610 units: direct materials, $9 per unit; direct labor, $23 per unit; variable manufacturing overhead, $16 per unit; total fixed manufacturing overhead costs, $15,250; variable selling and administrative costs, $2 per unit; total fixed selling and administrative costs, $9,150. There are no beginning inventories. What is the operating income using variable costing if 400 units are sold for $120 each? A. $4,400 B. $8,850 OC. $28,000 OD. $3,600