ABC Corporation makes a product with the following standard costs: The company reported the following results concerning this product in September. The company applies variable overhead on the basis of direct labor-hours. The direct materials purchases variance is computed when the materials are purchased. a. Compute the materials quantity variance. b. Compute the materials price variance. c. Compute the labor efficiency variance. d. Compute the direct labor rate variance. e. Compute the variable overhead efficiency variance. f. Compute the variable overhead rate variance