I already explained Encyclopedia analogy in LT 1 but I will add it above this. For this case, mutations could be one of these examples, Duplication, Deletion, Inversion, or translocation. For Duplication, it could be an extra part of the encyclopedia duplicated, so there are 2 parts. For Deletion, some of the parts of the information within the encyclopedia breaks off or an entire page, for inversion a section could be reversed then put back in the spot, and for translocation, when a random part of the book breaks off and attaches to another random part of the book.