The dendrogram is a graphical summary of the cluster solution. Cases are listed along
the left vertical axis. The horizontal axis shows the distance between clusters when they
are joined. Parsing the classification tree to determine the number of clusters is a
subjective process. Generally, you begin by looking for "gaps" between joinings along the
horizontal axis. Starting from the right, there is a gap between 20 and 25, which splits the
automobiles into two clusters. There is another gap from approximately 10 to 15, which
suggests 6