\documentclass{article}
\usepackage{graphicx}
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\usepackage[margin=35mm]{geometry}
\usepackage{amsmath}

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\lhead{\sf Logic and Mechanized Reasoning}
\rhead{\sf Fall 2021}


\newcommand{\problem}[1]{\subsection*{Problem #1}}
\newcommand{\answers}[1]{{\Large Answers #1\\ \medskip}}
\newcommand{\student}[2]{by #1 #2\\ \medskip}

\begin{document}
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\begin{center}
\answers{X} % replace by assignment number
\student{Firstname}{Lastname} % replace by first name and last name
\end{center}

\problem{1}

This is an example answer.

\problem{2}

\problem{3}

\problem{4}

\problem{5}

\problem{6}

\end{document}