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\begin{center}\textbf{Problem Set 3 \hspace{.7in} Graph Theory \hspace{.7in} Due 10/29/15} \end{center}

\noindent Four of these problems will be graded, with each problem worth 5 points.  Clear and complete justification is required for full credit.  You are welcome to discuss these problems with anyone and everyone, but must write up your own final submission without reference to any sources other than the textbook and instructor. 

\begin{enumerate}
\item Loosely speaking, every tree has at least 2 vertices of degree 1.  Refine this statement and give a good proof.

\item Do Problem G21 from Marcus.

\item Do Problems G33 and G34 from Marcus.

\item Do Problems H16 and H17 from Marcus.

\item Do Problem I20 from Marcus.

\item Do Problem I21 from Marcus.

\item Do Problems I34 and I 35 from Marcus.

\item Do Problem J38 from Marcus.

\item Do Problems J39-J42 from Marcus.

\end{enumerate}

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