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What If?: Serious Scientific Answers to Absurd Hypothetical Questions

I enjoyed this book. I like XKCD a lot and partly because Munroe is so danged smart about everything. He’s managed to put that all together in this fun compendium of weird questions people have asked him, split into ones he really tries to answer and a few he just illustrates for the heck of it. Mostly fun, sometimes I feel it’s handwavey. Always enjoyable and great illustrations and humor you’ve come to expect from XKCD.