Using the perpetual inventory system, journalize the entries for the following selected transactions: (a) Sold merchandise on account for $12,000, terms n/30. The cost of the merchandise sold was $6,500. (b) Sold merchandise to customers who used MasterCard and VISA, $9,500. The cost of the merchandise sold was $5,300. (c) Sold merchandise to customers who used American Express, $2,900. The cost of the merchandise sold was $1,700. (d) Paid an invoice from First National Bank for $385, representing a service fee for processing MasterCard and VISA sales, (c) Received $2,825 from American Express Company after a $75 collection fee had been deducted. Magnesium XP Cost Units 1 May 3 Purchase $130 10 Purchase 136 19 Purchase 1421 Total $408 Assume that two units are sold on May 23 for $313 total. Determine the gross profit for May and ending inventory on May 31 using (a) FIFO, (b) LIFO, and (c) average cost methods