Dermody Snow Removal's cost formula for its vehicle operating cost is $2,900 per month plus $320 per snow-day. For the month of December, the company planned for activity of 15 snow-days, but the actual level of activity was 13 snow-days. The actual vehicle operating cost for the month was $7,980. The spending variance for vehicle operating cost in December would be closest to: Multiple Choice $280 F O $920 U $920 F O O $280 U