1. Trees (a) Give eight different examples of trees that have exactly three leaves. (b) Give an example of a tree that has 10 vertices, nine of which are leaves. (c) Give an example of an acyclic graph G (ie, G contains no cycles) with 20 vertices that is not a tree. 2. Degree Sequences. You are given two sequences of non-negative integers below. Decide which sequences below represent the degree sequence of some simple graph.