Novelli Corporation makes a product whose variable overhead standards are based on direct labor-hours. The quantity standard is 0.9 hours per unit. The variable overhead rate standard is $8.50 per hour. In September, the company produced 1,700 units using 1,520 direct labor-hours. The actual variable overhead rate was $9.30 per hour. The variable overhead efficiency variance for September is:

$93 U

$85 U

$93 F

$85 F