E9-10 (Algo) Calculating Variable Overhead Variances [LO 9-5] Parker Plastic, Incorporated, manufactures plastic mots to use with rolling office chairs, Its standard cost information for last year follows: Parker Plastic had the following octual results for the past year: Required: Caiculate Parker Plastic's variable overhead rate and efficiency variances and its over-or underapplied variable overhead. Note: Do not round intermediate calculations. Indicate the effect of each variance by selecting " F " for favorable, " U " for unfavorable, and "None" for no effect (li.e., zero variance)