Wharton Tooling uses a standard cost system to account for the costs of its one product. Variable overhead standards are 14 hours of labor at a standard rate of $9.15. Fixed overhead is applied at a rate of $150 per unit, based on budgeted production of 650 units. During July, Wharton Tooling produced 560 units. Payroll totaled $113,300 for 8,665 hours worked. Overhead incurred was $77,530 variable and $99,530 fixed. a. Calculate the variable overhead rate variance. (Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (i.e., zero variance). Do not round your intermediate calculations. Round your answer to 2 decimal places.)

b. Calculate the variable overhead efficiency variance. (Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (i.e., zero variance). Do not round your intermediate calculations. Round your answer to 2 decimal places.)

c. Calculate the fixed overhead spending variance. (Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (i.e., zero variance).)