17. U.S. Airfilter has hired you as a supply chain consultant. The company makes air filters for residential heating and air-conditioning systems. These filters are made in a single plant located in Louisville, Kentucky, in the United States. They are distributed to retailers through wholesale centers in 100 locations in the United States, Canada, and Europe. You have collected the following data relating to the value of inventory in the U.S. Airfilter supply chain: Quarter 1 January through March) Quarter 2 (April through June) Quarter 3 July through September) Quarter 4 (October through December) Sales (total quarter): United States Canada Europe 300 75 30 405 75 20 375 70 15 350 60 Cost of goods sold (total quarter) 280 295 340 350 50 40 60 Raw materials at the Louisville plant (end-of-quarter)