Ch5 Perpetual Inventory Method (optional & extra credit)) Please watch the video: https://www.youtube.com/watch? v=3j-CGB4f988 and study the pptx as attached. Key points to learn are as follows: 1. Gross Margin : Sales - COGS (Cost of Goods Sold) 2. Journal Entries associated with purchase and sales related transactions. Chapter 5 Exercises On September 1, Nixa Office Supply had an inventory of 30 calculators at a cost of $18 each. The company uses a perpetual inventory system. During September, the following transactions occurred. 9/6 Purchased 90 calculators at $22 each from York, terms net/30. 9/9 Paid freight of $90 on calculators purchased from York Co. 9/10 Returned 3 calculators to York Co. for $69 credit (including freight) because they did not meet specifications. 9/12 Sold 26 calculators costing $23 (including freight) for $31 each to Sura Book Store, terms n/30. 9/14 Granted credit of $31 to Sura Book Store for the return of one calculator that was not ordered. 9/20 Sold 30 calculators costing $23 for $32 each to Davis Card Shop, terms n/30