With the expectation of big domestic growth, Amazon plans to create 100,000 full-time positions in the U.S. over the next year and a half. We'll look at where the retailer expects to see growth and where its thousands of new employees are likely to be working. Next, we'll talk about a new study that says fitness trackers can be used for the early detection of health problems, and then cap off the show with our weekly numbers game, "Silicon Tally." This week's opponent: Alex Davies, the transportation editor at Wired.com.