Free books to download What If?: Serious Scienti

Randall Munroe left NASA in 2005 to start up his hugely popular site XKCD 'a web comic of romance, sarcasm, math and language' which offers a witty take on the world of science and geeks. It now has 600,000 to a million page hits daily. Every now and then, Munroe would get emails asking him to arbitrate a science debate. 'My friend and I were arguing about what would happen if a bullet got struck by lightning, and we agreed that you should resolve it . . . ' He liked these questions so much that he started up <i>What If</i>. <br /><br /><b>If your cells suddenly lost the power to divide, how long would you survive?</b><br /><br /><b> How dangerous is it, really, to be in a swimming pool in a thunderstorm?</b><br /><br /><b> If we hooked turbines to people exercising in gyms, how much power could we produce?</b><br /><br /><b> What if everyone only had one soulmate?</b><br /><br /><b>When (if ever) did the sun go down on the British empire? </b><br /><br /><b> How fast can you hit a spe