The following additional information is available for the labor costs in Question 3. Standard cost per unit of product 2.0 direct labor hours @ $25 per labor hour Actual use of direct labor is 13,500 hours @ $28 per hour The labor rate and the labor efficiency variances are: a. $40,500 U labor rate variance and $32,500 F labor efficiency variance b. $44,400 U labor rate variance and $36,400 F labor efficiency variance c. $32,500 F labor rate variance and $40,500 U labor efficiency variance d. None of the above