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\lhead{Joe Schmoe}
\chead{ECE~557~--- Thursday, 1:30~--- T.~Pavlic (instructor)}
\rhead{Pre-lab 0}
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\usepackage{varioref}
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\centerline{\fbox{\parbox{0.75\columnwidth}{\textbf{SPECIAL NOTE:} If
you notice a few ``\textbf{??}'' in funny places in your document (e.g.,
the footer may say ``\textbf{Page 1 of ??}''), then run \LaTeX{} again.
That information was not available in the first pass, but it will be
filled in properly in the second pass.}}}

\section{Manually Numbered Answers}

\begin{itemize}

        \item[2.1.] Here is my answer to question~2.1 of the text of the
                book. This question has sub-parts, and so I use another
                list to answer them.
                %
                \begin{enumerate}[a)]

                        \item Answer to first sub-part.

                        \item Answer to second sub-part requires an
                                image.\\

                                %\centerline{\includegraphics[width=0.5\columnwidth]{figurename}}
                                \centerline{\fbox{Normally, I would do
                                \textbackslash\texttt{includegraphics}\{\texttt{figurename}\}
                                here.}}

                \end{enumerate}

        \item[2.7.] Here is my answer to question~2.7. It also has
                sub-parts, but for some reason they're given with roman
                numerals, and so I'll use lowercase roman numerals here
                too.
                %
                \begin{enumerate}[i)]

                        \item Answer to first sub-part.

                        \item Answer to second sub-part.

                \end{enumerate}

\end{itemize}

\section{Automatically Numbered Answers}

\begin{enumerate}

        \item This question asks me to list things, and so I give
                an unnumbered/unlettered list.
                %
                \begin{itemize}

                        \item First item in the list.

                        \item Second item in the list.


                \end{itemize}

        \item This question requires me to list a
                mathematical equation, which I can refer to as
                \autoref{eq:trigcalc}.
                %
                \begin{equation}
                        \frac{\sin(2\pi T)}{2\pi}
                        =
                        \int_0^T \cos(2\pi t) dt
                        \label{eq:trigcalc}
                \end{equation}
                %
                Using an \texttt{equation*} environment instead of an
                \texttt{equation} environment gets rid of the equation
                numbering. Math can also be listed in-line, like $x =
                5$.

\end{enumerate}

\section{Question 5}

Or you could just give each answer its own section.

\setcounter{secnumdepth}{1}

\section{Automatically Numbered Sections}

If you get rid of the \texttt{secnumdepth} line in the preamble (or set
it to a positive number), your \textbackslash\texttt{section} commands
automatically get numbered.

\section{Another Numbered Section}

So that's another option.

\section*{Removing Numbers}

Even when \texttt{secnumdepth} is left to its default positive value,
using \textbackslash\texttt{section*} instead of
\textbackslash\texttt{section} will remove numbering for that section.

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