Donovan Company incurred the following costs while producing 500 units: direct materials, $10 per unit; direct labor, $25 per unit; variable manufacturing overhead, $15 per unit; total fixed manufacturing overhead costs, $10,000, variable selling and administrative costs, $5 per unit, total fixed selling and administrative costs, $7,500. There are no beginning inventories What is the unit product cost using variable costing? OA $50 per unit OB. $55 per unit OC. $70 per unit OD. $90 per unit