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Jan 3. Sold merchandise for $21,800 plus 8% sales tax to retail cash customers. The cost of merchandise sold was $ 13,000. Jan 16. Sold merchandise, on account to Keystone Co, $16,500, terms FOB shipping point, 1/10, n/30. The cost of merchandise sold was $ 10,000. Jan 18. Issued a credit memo for $2,000 to Keystone Co, for merchandise returned from sale on Jan 16. The cost of the merchandise returned was $1,200. Jan 25. Received check for amount due from Keystone Co. Jan 30. Purchased merchandise from Folts Co., $8,000, terms FOB destination, 2/10, n/30. Feb 4. Issued a debit memo to Folts Co., for $ 1,500 of merchandise returned from purchase on Jan 30. Feb 6. Paid Folts Co. for amount due