Perpetual and Periodic Inventory Systems Below is a list of inventory systems options. a. Perpetual inventory system b. Periodic inventory system c. Both perpetual and periodic Inventory systems Required: Select the appropriate inventory systems(s) for each of the following: 1. Only revenue is recorded as sales are made during the period; the cost of goods 2. Cost of goods sold is determined as each sale is made. 3. Inventory purchases are recorded in an inventory account. 4. Inventory purchases are recorded in a purchases account.