Required information The Foundational 15 (Algo) [LO9-1, LO9-2, LO9-4, LO9.5, LO9-6] [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 19,000 units. However, during March the company. actually produced and sold 24,000 units and incurred the following costs: a. Purchased 160,000 pounds of raw materials at a cost of $7.20 per pound. All of this material was used in production. b. Direct-laborers worked 72,000 hours at a rate of $18.00 per hour, c. Total variable manufacturing overhead for the month was $336,960. d. Total advertising, sales salaries and commissions, and shipping expenses were $374,000,$540,000, and $285,000, respectively. oundational 910 (Algo) What is the variable overhead efficiency variance for March? (Indicate the effect of each variance by selecting "F" for favorable, " for unfavorable, and "None" for no effect (i.e., zero variance.). Input the amount as a positive value.)