LLL's standard cost card follows: Standard Quantity 0.6 Standard Rate Standard Unit Cost $0.48 Variable manufacturing overhead $0.80 During August, LLL had the following actual results: Units produced and sold Actual variable overhead Actual direct labor hours 26,100 $ 9,570 16,800 Required: Compute LLL's variable overhead rate variance, variable overhead efficiency variance, and over- or underapplied variable overhead. (Do not round intermediate calculations. Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance).) Variable Overhead Rate Variance Variable Overhead Efficiency Variance Variable Overhead Spending Variance