Q. A.

When Jeff Bezos, the C.E.O. of Amazon, told "60 Minutes" this week that his company was experimenting with having drones deliver its packages, he seemed to be conjuring up a future in which fleets of flying machines would tote most of our purchases, and in which ordinary delivery people would become obsolete. But even if Amazon's Prime Air does work, and if drone delivery eventually becomes adopted more widely, it's not likely to wreck the delivery business as we know it.