please answer parts a, b & c. thank you!

OH variances The manager of the Texas Department of Transportation has determined that it typically takes 30 minutes for the department's employees to register a new car. in Bexar County, the predetermined fixed overhead rate was computed on an estimated 6,000 direct labor hours per month and is $9 per direct labor hour, whereas the predetermined variable overhead rate is 33 per direct labor hour. Duringluly, 11,280 cars were registered in Bexar County, and 5,700 direct labor hours were worked in registering those vehicles, For the month, variable overhead was $16,620 and fixed overhead was $54,480; . Note: In answering the following questions, do not use negative signs with your answers. a. Compute overhead variances using a four-variance approach. b. Compute overhead variances using a three-variance approach. OH Spending Variance Actual OH - Budget at Actual =OH Spending Variance c. Compute overhead variances using a two-variance approach. rlease answer all parts of the