please show all calculations by hand, thank you.

NSF Lube is a fast growing chain of oll-change stores. The following data are available for last year's services. NSF Lube performed 474,700 oil changes last year. It had budgeted 432 200 oil changes, averaging 15 minutes each. Standard variable labor and support costs per oil change were as follows. Direct oil specialist services: 15 minutes at $24 per hour Variable support staff and overhead: 7.0 minutes at $18 per hour $6.00 2.10 Fixed overhead costs: Annual budget $1,036,200 Fixed overhead is applied at the rate of $2.40 per oil change. Actual oil change costs: Direct oil specialist services: 474,700 changes averaging 13 minutes at $27 per hour Variable support staff and overhead: 0.12 labor-hours at $16 per hour x 474,700 changes Fixed overhead $2,776,995 911, 424 1,215,000 13 Required: a. Prepare a cost variance analysis for each variable cost for last year. b. Prepare a fixed overhead cost variance analysis