Theorem 8.3.3. Derivation of Statistics for Exponential Distribution and Plotting.
\begin{equation*}
\mu = \frac{1}{\lambda}
\end{equation*}
\begin{equation*}
\sigma^2 = \mu^2
\end{equation*}
\begin{equation*}
\gamma_1 = 2
\end{equation*}
\begin{equation*}
\gamma_2 = 9
\end{equation*}