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Part A - Inventory Costing Methods (12 marks) During January, a company that uses a perpetual inventory system had beginning inventory_ purchases and sales as follows. Required: Compute the cost of inventory on January 31 and the cost of goods sold during January using the following methods: 1. FIFO, 2. Weighted average. Beginning inventory Jan. 5 Purchase Jan. 10 Sale Jan. 15 Jan. 25 Purchase Sale Units 100 40 60 70 50 Cost per Unit $10 12 13 Part B-Effect of Error in Ending Inventory (2 marks) Required: What is the effect of understating the ending inventory balance on the income statement? Part C-Lower of Cost or Market (2 marks) A company normally sells its product for $22 per unit. However, the selling price has fallen to $15 per unit. The selling costs per unit are $3. This company's current inventory consists of 300 units purchased at $16 per unit. Required: Calculate the value of this company's inventory at the lower of cost or net realizable value