Job no. 811 involved the production of 200 units of product MF. The total standard and actual costs for materials and direct labor on this job are shown below: Standard Actual Direct materials: Standard: 520 pounds @ $3.40 per pound $1,768 Actual: 540 pounds @ $3.45 per pound $1,863 Direct labor: Standard: 220 hours @ $10 per hour $2,200 Actual: 213 hours @ $11 per hour $2,343 Compute the following cost variances for job no. 811. Indicate whether each variance is favorable (F) or unfavorable (U). a. Labor rate variance: $ b. Labor efficiency variance: $