Mondo Snow Removal's cost formula for its vehicle operating cost is $1,220 per month plus $657 per snow-day. For the month of January, the company planned for activity of 26 snow-days, but the actual level of activity was 30 snow-days. The actual vehicle operating cost for the month was $20,520. The activity variance for vehicle operating cost in January would be closest to:

$2,218F

$2,628U

$2,218U

$2,628F