1670 Marigold's Place recorded the following data: Units Date Received Sold On Hand Unit Cost 1/1 Inventory 630 $2.30 1/8 Purchase 1040 1670 3.20 1/12 Sold 1220 450 The weighted-average unit cost of the inventory at January 31 is: O $2.76 O $2.30 O $2.86 O $3.60