[The following information applies to the questions displayed below.] Preble Company manufactures one product. Its variable manufacturing overhead is applied to production based on direct labour-hours, and its standard costs per unit are as follows: Direct materials: 6 kg at $8.00 per kg $ 48.00 Direct labour: 3 hours at $14 per hour 42.00 Variable overhead: 3 hours at $5 per hour 15.00

Total standard cost per unit $ 105.00

The company planned to produce and sell 19,000 units in March. However, during March the company actually produced and sold 24,000 units and incurred the following costs: aPurchased 160,000 kg of raw materials at a cost of $7.20 per kg. All of this material was used in production. bDirect labour: 60,000 hours at a rate of $15 per hour. cTotal variable manufacturing overhead for the month was $336,600. 8. What is the variable overhead rate variance for March? (Round the actual overhead rate to two decimal places. Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance.).)