Parker Plastic, incorporated, manufactures plastic mats to use with rolling office chalits. its standard cost information for last year follows: Parker Plastic hod the following octual tesults for the past year Required: Calculate Parker Plastic's variable overhead rate and efficiency variances and its over- or underapplied variable overtheod. Note: Do not round intermediate calculations. Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavornble, and "None" for no effect (i.e., zero variance)