Different management levels in Bates, Inc., require varying degrees of managerial accounting information. Because of the need to comply with the managers' requests, four different variances for manufacturing overhead are computed each month. The information for the September overhead expenditures is as follows: Budget Budgeted output units 3,200 units Budgeted fixed manufacturing overhead $20,000 Budgeted variable manufacturing overhead $5 per direct labor hour Budgeted direct manufacturing labor hours 2 hours per unit Actual Actual units manufactured 3,400 Fixed manufacturing costs incurred $26,000 Direct manufacturing labor hours used 7,200 Variable manufacturing costs incurred $35,600 Required) 1) Variable manufacturing overhead variance analysis a. Compute variable overhead flexible budget variance. b. Compute variable overhead spending variance. c. Compute variable overhead efficiency variance. 2) Fixed manufacturing overhead variance analysis a. Compute fixed overhead flexible budget variance. b. Compute fixed overhead spending variance. c. Compute fixed overhead efficiency variance. d. Compute fixed overhead production-volume variance. I 3) Explain why the company has the fixed overhead production-volume variance you computed above.