The following labor standards have been established for a particular product: Standard labor-hours per unit of output 8. 1 hours Standard labor rate $ 14.40 per hour The following data pertain to operations concerning the product for the last month: Actual hours worked 8, 700 hours Actual total labor cost $ 129, 195 Actual output 1, 000 units What is the labor efficiency variance for the month? Multiple Choice O $8,910 U O $12,555 F O $12,555 U $8,640 U