Required information [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 labor-hours and its standard cost card per unit is as follows: The planning budget for March was based on producing and selling 20,000 units. However, during March the company actually produced and sold 25,500 units and incurred the following costs: a. Purchased 170,000 pounds of raw materials at a cost of $7.20 per pound. All of this material was used in production. b. Direct laborers worked 73,000 hours at a rate of $14 per hour. c. Total variable manufacturing overhead for the month was $427,050. 4. What is the variable overhead rate variance for March? (Round the actual overhead rate to two decimal places. Indicate the effect f each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance.). Input all Imounts as positive values.)