Retriever Company recently used 14,000 labor hours to produce 7,600 completed units. According to manufacturing specifications, each unit is anticipated to take two hours to complete. The company's actual payroll cost amounted to $158.200 If the standard cost per hour is $11.10, the company's labor efficiency variance is O $13,320 F None these $2,800 F $2,800 U. $13,320 U