Wisner Fabrication prepares its budgets on the basis of standard costs. Variances are analyzed and reported monthly. There are no materials inventories. The following information relates to the current period: Actual costs and activities for the month follow: Required: Prepare a cost variance analysis for the variable costs. Note: Indicate the effect of each variance by selecting "F" for favorable, or " U " for unfavorable. If there is no effect, do not select either option