Zimmerman Corporation uses a standard cost system for the production of its radios. The direct labor standard for each radio is 0.9 hours. The standard direct labor cost per hour is $7.20. During the month of August, Zimmerman's radio production used 6,900 direct labor-hours at a total direct labor cost of $48,708. This resulted in production of 6,600 radios for August. What is Zimmerman's labor rate variance for August? $2,160 Unfavorable $972 Favorable $1,188 Unfavorable $6,912 Unfavorable