Ortman Corporation makes a product with the following standard costs: Standard Price or Rate Direct materials Direct labor Variable overhead Standard Quantity or Hours 6.9 liters 13 hours 13 hours $14.00 per liter $19.00 per hour $100 per hour The company reported the following results concerning this product in May: Actual output Raw materials used in production Actual direct labor-hours Purchases of raw materials Actual price of raw materials purchased Actual direct labor rate Actual variable overhead rate 1,900 units 12,920 liters 2,390 hours 14,500 liters $ 710 per liter $18.20 per hour $0.50 per hour The company applies variable overhead on the basis of direct labor hours. The direct materials purchases variance is computed when the materials are purchased. The labor rate variance for May is: O $1,939F $1,912 $1,912 F $1,939 U