During the month of June, Ace Incorporated purchased goods from two suppliers. The sequence of events was as follows: June 3 Purchased goods for $4,100 from Diamond Inc. with terms 2/10, n/30. 5 Returned goods costing $1,100 to Diamond Inc. for credit on account. 6 Purchased goods from Club Corp. for $1,000 with terms 2/10, n/30. 11 Paid the balance owed to Diamond Inc. 22 Paid Club Corp. in full. Required: Assume that Ace uses a perpetual inventory system and that the company had no inventory on hand at the beginning of the month. Calculate the cost of inventory as of June 30.