Download or read book By the Numbers 2. 0 written by National Geographic Society (U.S.) and published by National Geographic Books. This book was released on 2016 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents number-related facts, including the estimated age of the universe, the average speed of a woodpecker's pecks, the amount of protein in a grasshopper, the number of red blood cells in a human body, and the melting point of gold.