Calculate the Merchandise Inventory balance at the end of the period, given these transactions. The company uses a perpetual inventory system and there was no beginning inventory balance. 7/1 Purchased $1,800 of merchandise on account. 7/7 Sold merchandise to a customer for $1000 with terms 1/10;n/30. The cost of the merchandise is $300. 7/10 The customer returned merchandise to the company received a credit for $100. The cost of the merchandise returned was $40. 7/11 The customer paid the full amount owed within the discount period.