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\begin{document}

\title[101 Homework \#16]{Math 101: Algebra I \\ Homework, Day \#16}
\date{Assigned Friday, 7 October 2016; due Monday, 10 October 2016}

\maketitle

\begin{problab}{JV16.A}
Let $R$ be a domain, and let $I \subseteq R$ be an ideal.  Show that $I$ is a principal ideal if and only if $I$ is isomorphic to $R$ as a $R$-module.
\end{problab}

\end{document}