Parker Plastic, Incorporated, manufsctures plastic mats to use with rolling office chairs. 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 elficiency varlances and its over- or underapplied variable overhead. Note: Do not round intermediote calculations. Indicote the effect of each varionce by selecting "F" for fovorable, "U" for unfovoroble, and "None" for no effect (i.e, zero voriance)