Dubberly Corporation's cost formula for its manufacturing overhead is $31.900 per month plus $65 per machine-hour. For the month of March, the company planned for activity of 8,160 machine-hours, but the actual level of activity was 8.010 machine-hours. The actual manufacturing overhead for the month was $586,270. The spending variance for manufacturing overhead in March would be closest to: Multiple Choice $23.970 U O $23.970 F $33,720 F O $33.720 U