**Readings Check section 11.1**

Read Section 11.1

Type in the answers below each question and email the completed document to me, or print out the document and fill it out by hand and email a scan or photo of it to me.

1) What is the relationship between the vertices and the edges in a graph?

2) What is the difference between a directed graph and an undirected graph?

3) What does it mean for a vertex x to be adjacent to a vertex y?

4) What is the edge {a, a} called?

5) What is an isolated vertex?

6) In figure 11.4, what is the length of the walk a ® d ® b ® c ® f ? Is it closed or open?

7) What is a circuit?

8) In an undirected graph G, does the existence of a trail from vertex a to vertex b guarantee the existence of a path from a to b? [p. 517]

9) What does it mean for a graph to be connected?

After submitting this form, go on to watch the videos, read the notes, and start the homework assignment for section 11.1. Ask any questions that arise at any point in the process. When the homework assignment is done, and you feel that you have a solid understanding of the homework and the section, then take the quiz for section 11.1.