Buy and Walmart sell through both traditional retail stores and the Internet, while Amazon sells only through the annual reports for all three companies is as follows (in millions): Sales Net cash flows from operating activities Amazon $160,408 Best Buy Walmart $43,638 $523,964 Purchases of property, plant, and equipment 38,514 (16,861) 2,565 (743) 25,255 (10,705) a. Determine the free cash flow for all three companies. Enter answers in millions. Amazon: $ 21,653 Best Buy: $ 1,822 Walmart: $ 14,550 b. Compute the ratio of free cash flow to sales for all three companies. Round percentages to one decimal place. Amazon: Best Buy: Walmart: % % % How does Amazon.compar the other two