The following labor standards have been established for a particular product Standard labor-hours per unit of output 8.6 hours Standard labor rate $ 12.40 per hour The following data pertain to operations concerning the product for the last month: Actual hours worked 6400 hours Actual total labor cost $ 76,800 Actual output 850 units What is the labor efficiency variance for the month? 0$13,844 U O $10.920 F O $13,844 F O $11.284 F