the question a and b I know how to do it,but I don't know how to answer the question C,can you help me?thank you

Kitchen Electrics uses a perpetual inventory system. The following are three recent merchandising transactions. Apr. 10 Apr. 15 Apr. 20 Purchased 10 refrigerators from Polar Co. on account. Invoice price, S600 per unit, for a total of $6,000. The terms of purchase were 2/10, 1/30. Sold one of these refrigerators for $900 cash. Paid the account payable to Polar Co. within the discount period. Instructions a. Prepare journal entries to record these transactions assuming that Kitchen Electrics record purchases of merchandise at: 1. Net cost 2. Gross invoice price b. Assume that Kitchen Electrics did not pay Polar Co. within the discount period but instead paid the full invoice price on May 10. Prepare journal entries to record this payment assuming that the original liability had been recorded at: 1. Net cost 2. Gross invoice price c. Assume that you are evaluating the efficiency of Kitchen Electric's bill-paying procedures. Which accounting method-net cost or gross invoice price-provides you with the most use- ful information? Explain. Date. Journal entries Accounts title Accounts payable creclit may. 10 debit 5680 purchase discounts taken 120 cash 60 May. 1o 6000 Accounts payable. cash 6000 A3 Date. Debit credit Apr.lo 6000 Account stitle Inventory Accounts payable cash sales Gooo Apr.is Poo poo Apr.15 cost of goods Goo Inventory 600 Apr. 30 6000 Accounts payable cash Purchase discounts taken 6880 120 AL Date. credit. Debit 5880 Aprlo. 5880 Apr.15. poo Journal Entries accounts title. Inventory Accounts payable cash sale revenue cost at goods Inventory Acccuents payable cash poo Apr is $88 588 Apr.20. 5880 5880