The inventory records for Radford Co. reflected the following:

Beginning inventory @ May 1	2100 units @ $5.80
First purchase @ May 7	2200 units @ $6.00
Second purchase @ May 17	2400 units @ $6.10
Third purchase @ May 23	2000 units @ $6.20
Sales @ May 31	6600 units @ $7.70

What is the amount of gross margin assuming the weighted-average inventory cost flow method? (Round your intermediate calculations to two decimal places.)