Partridge Bookstore had 500 units on hand at January 1, costing $9 each. Purchases and sales during the month of January were as follows: Date Purchases Sales Jan. 14 375 $14 17 250 @$10 25 29 250 $11 260 $16 Partridge does not maintain perpetual inventory records. According to a physical count, 365 units were on hand at January 31. The cost of the inventory at January 31, under the FIFO method is: $3,285. $3,650. $3,900. $4,015.