thornton universal sales' cost of goods sold (cogs) average $2,000,000 per month, and it keeps inventory equal to 50% of its monthly cogs on hand at all times. using a 365-day year, what is its inventory conversion period? a. 14.4 days b. 16.7 days c. 13.0 days d. 15.2 days e. 11.7 days