Parker Plastic, Incorporated, manufactures plastic mats to yse 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 Parket Plastic's variable overhead rate and efficiency vaniances and its over-or underapplied variable overhead. Note: Do not round intermediate calculations. Indicote the effect of each varionce by selecting "F" for fovornble, "U" for unfovorable, and "None" for no effect (i.e., zero variance)