Kropf Inc. has provided the following data concerning one of the products in its standard cost system. Variable manufacturing overhead is applied to products on the basis of direct labor-hours. Standard Quantity or Hours per Unit of Output 8.50 liters 0.60 hours Standard Price or Rate 0.60 hours $ 8.10 per liter $25.70 per hour $ 7.00 per hour Inputs Direct materials Direct labor Variable manufacturing overhead The company has reported the following actual results for the product for September: Actual output Raw materials purchased Actual cost of raw materials purchased Raw materials used in production Actual direct labor-hours Actual direct labor cost Actual variable overhead cost 10,700 units 93,100 liters $771,500 90,960 liters 6,000 hours $160,302 $ 35,414 Required: a. Compute the materials price variance for September. b. Compute the materials quantity variance for September. c. Compute the labor rate variance for September. d. Compute the labor efficiency variance for September. e. Compute the variable overhead rate variance for September. f. Compute the variable overhead efficiency variance for September. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)