Porter Company uses Standard costs or its manufacturing division. Standards specify 0.1 direct labor hours per unit of product. The allocation base for variable overhead costs is direct labor hours. At the beginning of the year, the static budget for variable overhead costs included the following data: Production volume 6,000 units Budgeted variable overhead costs. $16,000 At the end of the year, actual data were as follows: Production volume. 4,100 units Actual variable overhead costs. $15,200 Actual direct labor hours (DLHr)500 hours What is the variable overhead efficiency variance? (Round any intermediate calculations to the nearest cent, and your final answer to the nearest dollar.) Answer: $2400U ***please show explanation and work for this