How to understand this kind of question? It is difficult for me~ Thank you~

Workshop on Inventory, Doubtful Debts and Recorrection of Financial Statements The following transactions relate to Cybertrax Trading. The Inventory balance at 1 May was $7500. Date (2018) Transactions 2-May Purchased inventory costing $2,000, terms 2/14, n/30. is -May Returned defective goods, which cost $400. 10- ay Sold goods for $1,200 (cost price $850), collecting cash of $500. Credit terms on the remainder of the goods sold were 2/10, n/30. 14-May Paid the amount owed on the 2 May purchase. 26-May Sales of $60 (cost price $40) were returned. These related to the 10 May sale, and a cash refund was given. 31-May A stock-take showed $8200 inventory on hand d 00 Vt oh Required: (a) (ii) (b) Prepare general journal entries (narrations not required) for the above transactions assuming: a periodic inventory system is used; (including entries to record COGS at end of May. a perpetual inventory systems is used Prepare Inc me Statements for May under each system