Raw Material Inventory Work in Process Inventory Finished Goods Inventory Total Inventory Net Sales Cost of Goods Sold Gross profit Gross profit ratio (All amounts in millions) 2017 2016 2015 2014 377 391 427 399 0 0 0 0 525 549 566 617 902 940 993 1,016 7,890 7,961 0,082 4,831 5,181 5,300 3,059 2,780 2,805 38.84 34.90 34.41 Required: a. Calculate the cost of goods manufactured for 2017, 2016, and 2015. b. Calculate the total amount of combined cost incurred in 2017, 2016, and 2015 for raw material direct labor, and manufacturing overhead c. Calculate the ratio of cost of sales to net sales for 2017, 2016, and 2015 d. Calculate the inventoly turnover and day's sales in Inventory for 2017 2016 and 2015