Phillips Supply uses a periodic inventory system but needs to determine the approximate amount of inventory at the end of each month without taking a physical inventory. Phillips has provided the following inventory data. a. Estimate the cost of goods sold and the cost of the July 31 ending inventory using the retail method of evaluation. (Round your intermediate calculations to 2 decimal places.) Phillips Supply uses a periodic inventory system but needs to determine the approximate amount of inventory at the end of each month without taking a physical inventory. Phillips has provided the following inventory data. a. Estimate the cost of goods sold and the cost of the July 31 ending inventory using the retail method of evaluation. (Round your intermediate calculations to 2 decimal places.)