21. Automobile Company produces a single product, a special radio. Each radio sells for $28, and the company sells 500,000 radios each year. Unit cost data are presented below: Variable Fixed Direct material. $6.00 Direct labor $5.00 Manufacturing overhead $2.00 $7.00 Selling & administrative $4.00 $3.00 The unit product cost of radios under variable costing is: * (1.5 Points) $17 $27 $20 $13