Schultz, Incorporated bases variable manufacturing overhead on direct labor hours. Below are the company's manufacturing overhead standards: Standard hours per unit 2.5 Standard rate per hour $6 During the current period, Schultz produced 3860 units of product, using 9,200 labor hours. Total variable manufacturing overhead for the period was $52,400. Schultz's variable manufacturing overhead rate variance and efficiency variance for the period are closest to: a. Variable Manufacturing Overhead Variable Manufacturing Rate Variance Overhead Efficiency Variance $ 2,800 U $ 2,700 F b. Variable Manufacturing Overhead Variable Manufacturing Rate Variance Overhead Efficiency Variance $ 2,800 F $ 2,700 U O c. Variable Manufacturing Overhead Variable Manufacturing Rate Variance Overhead Efficiency Variance $ 2,800 U $ 2,700 U d. Variable Manufacturing Overhead Variable Manufacturing Rate Variance Overhead Efficiency Variance $ 2,800 F $ 2,700 F