Strain Corporation makes a product with the following standard costs: Standard Quantity or Hours Standard Price or Rate Direct materials 2.5 grans $1.00 per gram Direct labor 0.7 hours $ 9.00 per hour Variable overhead 0.7 hours $ 3.00 per hour The company reported the following results concerning this product in June. Actual output Raw materials used in production Actual direct labor-hours Purchases of raw materials Actual price of raw materiale purchased Actual direct labor rate retual variable overhead rate 3,000 units 11,370 grams 1.910 hours 12.100 Grans 1.20 per gram 11.40 per hour 2.10 per hour $ 5 $ 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 variable overhead efficiency variance (VOH EV) for June is: a $380 F b. $570 F c. $380 U d. $570 U