NSF Lube is fast-growing chain of oil-change stores. The following data are available for last year's services: Lube performed 472,200 oil changes last year. It had budgeted 433,200 oil changes, averaging 12 minutes each. andard variable labor and support costs per oil change were as follows: Direct oil specialist services: 12 minutes at $23 per hour Variable support staff and overhead: 6.0 minutes $4.60 2.0 $20 per hour Fixed overhead costs: Annual budget $1,037,200 Fixed overhead is applied at the rate of $3.00 per oil change. Actual oil change costs: $3.887.780 1,133,280 1,290,000 Direct oil specialist services: 472,200 changes averaging 19 minutes at $26 per hour Variable support staff and overhead: 0.16 labor-hours at $15 per hour x 472,200 changes Fixed overhead Required: a. Prepare a cost variance analysis for each variable cost for last year. (Do not round intermediate calculations. Indicate the effect of each variance by selecting "F" for favorable, or "U" for unfavorable. If there is no effect, do not select either option.) Efficiency Total Variance Price Variance Variance Oil specialist Variable overhead b. Prepare a fixed overhead cost variance analysis. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect.) Price variance Production volume variance Fixed overhead cost variance