Transcript text: Refer to the following graph. Determine whether the sequence of vertices is (a) a walk, (b) a path, and (c) a circuit in the graph.
$\mathrm{E} \rightarrow \mathrm{C} \rightarrow \mathrm{A} \rightarrow \mathrm{D} \rightarrow \mathrm{A} \rightarrow \mathrm{E}$
(a) Is this sequence a walk?