Hammer Framing's cost formula for its supplies cost is $1,640 per month plus $9 per frame. For the month of August, the company planned for activity of 572 frames, but the actual level of activity was 573 frames. The actual supplies cost for the month was $7,080.

The supplies cost in the planning budget for August would be:

a. $7,080.

b. $7,068.

c. $6,788.

d. $6,797.