7 DES140 Wisteria Co produces snowboards and uses a standard cost system Variatide overhead mapped using direct labor and allowed for each unit are 52 hours of labor at a standard variable overhead rate of $740 During December, Watena Ca produced 3.050 snowboards Materials purchases totaled 21,300 pounds at a total cost of $224780 Matenals usage tousled 21,000 pounds Payroll totaled $183,720 for 17140 hours worked. Vanable overhend incurred totaled $123,566 a. Calculate the variable overhead rate variance (Do not round your intermediate calculations. Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (ie., zero variance).) b. Calculate the variable overhead efficiency variance. (Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (ie., zero variance). Do not round your intermediate calculations and round your final answer to the nearest whole dollar amount.)