4. The data below relate to a product of AirWay Company. Standard costs: Labor, 3 hours at $15 per hour Variable overhead at $8 per labor hour Budgeted fixed production costs Budgeted production for the year Actual results were: Production Labor, 10,360 hours Overhead incurred ($142,700 fixed) Required: $45 per unit $24 per unit $140,000 per year 4,000 units 3,600 Units $160,580 $222,200 15.50 (Be sure to indicate whether the variances are favorable or unfavorable.) a. What is the variable overhead efficiency variance? b. What is the variable overhead price variance? c. What is the fixed overhead budget variance? d. What is the fixed production volume variance?