Hulk sells new and refurbished auto parts exclusively to auto dealers. Hulk purchases inventory from distributors at trade conventions. Each time Hulk makes a purchase, the company records the supplier name, address, date, specific items purchased, price paid for each, and the total amount spent. Hulk later researches the inventory items to set the customer price. The company assigns an inventory number to each item purchased and records the customer price for each item. Hulk buys price tags and display supplies from Dooby, a company that sells them at trade conventions. All inventory and supplies purchases are immediately paid for with cash or with checks from a bank account in Hulk's name. All cash received from sales are also deposited to the same bank account. Hulk rents display space at dealer conventions several times a year. A deposit is always required, and the entire fee is due the day the convention starts. Hulk records the deposit and final payment, along with the convention's name and address, in the same worksheet on which purchases of inventory and supplies are recorded. Consider Hulk's processes regarding the purchasing inventory and supplies, renting display space, and paying for purchased items. In a well-designed Resources, Events and Agents (REA) diagram, what entities would reflect economic duality? a) Inventory and Purchases b) Display Space Rental and Cash Disbursements c) Cash and Cash Disbursements d) Purchases and Cash Disbursements