Russo Corporation manufactured 21,000 air conditioners during November. The overhead cost-allocation base is $34.25 per machine-hour. The following variable overhead data pertain to November Production Actual 21,000 units Budgeted 24,000 units Machine-hours 13,300 hours 14,400 hours Variable overhead cost per machine-hour $34.00 $34.25 What is the variable overhead spending variance? OA. $3,325.00 unfavorable OB. $3,600.00 favorable OC. $3,325.00 favorable D. $3,600.00 unfavorable