The inventory records for Radford Co. reflected the following

Beginning inventory @ May 1	2,200	units	@	$	6.00
First purchase @ May 7	2,300	units	@	$	6.20
second purchase @ May 17	2,500	units	@	$	6.30
Third purchase @ May 23	2,100	units	@	$	6.40
Sales @ May 31	6,900	units	@	$	7.90

Determine the amount of gross margin assuming the weighted average cost flow method. (Round your intermediate calculations to 2 decimal places.)