Parker Plastic, Incorporated, manufactures plastic mats to use with rolling office chalis. Its standard cost information for last year follows: Parker Plastic had the following actual results for the past year: Required: Calculate Parker Plastic's variable overhead rate and efficiency variances and its over- or underapplied variable overhead. Note: Do not round intermediote colculotions. Indicote the effect of each varionce by selecting "F" for favorable, "U" for unfovorable, and "None" for no effect (i.e. zero variance)