following labor standards have been established for a particular product Standard labor hours per unit of output Standard labor rates 6 hours 16.40per hour The following data pertain to operations concerning the product for the last month 4873hours Actual hours worked Actual total labor cost Actual output 84.490 BOOnits What is the labor efficiency variance for the month (rounded? 54.573F $6.6750 $4.5730 $6.675 F