Answers to questions you probably never thought to ask. If you randomly choose a number and say "bless you," what are the odds that the person you called just sneezed? Randall Munroe, the brilliant creator of xkcd.com, answers the craziest questions with high-level science and stunning creativity. From the number of people needed to meet the daily caloric needs of a Tyrannosaurus to the experience of swimming in a lunar lake: Illustrated with Munroe's famous stick figures, "What If?" offers original entertainment at the highest level. Now available in a new edition with additional chapters.