Courington Detailing's cost formula for its materials and supplies is $2,420 per month plus $9 per vehicle. For the month of August, the company planned for activity of 63 vehicles, but the actual level of activity was 33 vehicles. The actual materials and supplies for the month was $2,840. The spending variance for materials and supplies in August would be closest to: Multiple Choice $147 F $123 F $123 U $147 U