a) Define a rooted tree and the root of such a tree.
b) Define the parent of a vertex and a child of a vertex in a rooted tree.
c) What are an internal vertex, a leaf, and a subtree in a rooted tree?
d) Draw a rooted tree with at least 10 vertices, where the degree of each vertex does not exceed 3. Identify the root, the parent of each vertex, the children of each vertex, the internal vertices, and the leaves.