The inventory records for Radford Co. reflected the following

Beginning inventory @ May 1	1,600	units	@	$	4.80
First purchase @ May 7	1,700	units	@	$	5.00
second purchase @ May 17	1,900	units	@	$	5.10
Third purchase @ May 23	1,500	units	@	$	5.20
Sales @ May 31	5,100	units	@	$	6.70

Determine the amount of gross margin assuming the weighted average cost flow method.

$18,360

$26,520

$8,517

$7,650