Information related to Churchill Corporation's inventory for December is given below: Purchases Unit Total Cost Cost $50 $7,500 Sales Selling Units Price/Unit Total Sales $ Units 150 10 $150 $1,500 Dec 1 Dec 7 Dec 10 Dec 12 Dec 20 Dec 17 Dec 30 Beginning inventory Sale Purchase Purchase Purchase Sale Purchase 70 50 40 $47 $46 $45 $3,290 $2,300 $1,800 200 $155 $31,000 25 $53 $1,325 Required (parts a, b & c): a) Assume Churchill Corporation uses the periodic inventory system. Calculate the ending inventory in units and total dollars at December 31 using average cost. (show calculations) You are welcome to use the inventory worksheets provided, but please transfer your final answer to the space below. b) Assume Churchill Corporation uses the perpetual inventory system. Calculate the ending inventory in units and total dollars using FIFO. Show calculations to receive full marks (either here or on the inventory sheets). You are welcome to use the inventory worksheets provided, but please transfer your final answer to the space below. c) Using the data from part b, what is the cost of goods sold (COGS), gross profit and gross profit margin for the month of December? Show calculations to receive full marks (either here or on the inventory sheets). You are welcome to use the inventory worksheets provided, but please transfer your final answer to the space below