Schlick Framing's cost formula for its supplies cost is $1,730 per month plus $11 per frame. For the month of August, the company planned for activity of 613 frames, but the actual level of activity was 618 frames. The actual supplies cost for the month was $8,670. The activity variance for supplies cost in August would be closest to:
a) $197 F
b) $197 U
c) $55 F
d) $55 U