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 company also established the following cost formulas for its selling expenses: The planning budget for March was based on producing and selling 28,000 units. However, during March the company actually produced and sold 34,000 urits and incured the following costs: a. Purchased 180,000 pounds of raw materials at a cost of $8.50 per pound. All of this material was used in production. b. Direct laborers worked 69.000 hours at a rate of $15.00 per hout. c. Total variable manufacturing overthead for the month was $565,110. d. Total advertising, soles salaries and commissions, and shipping expenses were $345,000,$525,000, and $255,000. respectively. 10. What is the varlable overhead efficiency variance for March? (Indicate the effect of eoch voriance by selecting "F" for favorable, " U for unfaverable, and "None" for no effect (i.e., zero variance.). Input the amount as a positive value.)