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Calculate, for the month of March, cost of sales and closing inventory assuming perpetual inventory system is in place, using the following inventory valuation methods: i- Weighted Average AVCO (7 marks) ii- First In First Out FIFO DateUnits Purchased Mar, |Balance: 300 units @ 01 3 each 8 marks Units Sold 150 units E 4 each 01 Mar 09 300 units 7 each 50 units 5 each 13 250 units 4 each 17 Mar 20 120 units @ 8 each