\documentclass{article}
\usepackage{graphicx}
\usepackage{amssymb}
\usepackage{epstopdf}
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\begin{document}

This is 2 and 2 test. 



\begin{figure}[hptb]
\begin{multicols}{2}
\begin{center}
\includegraphics[width=0.49\textwidth]{figures/fig1.eps}
\end{center}
\caption{Caption of figure 1.}
\label{Noise:ENC1}
\begin{center}
\includegraphics[width=0.49\textwidth]{figures/fig2.eps}
\end{center}
\caption{Caption of figure 2.}
\label{Noise:ENC2}
\end{multicols}
\end{figure}



Figure~\ref{Noise:ENC1} shows the distribution of average input noise per chip.
Figure~\ref{Noise:ENC2} shows the distribution of average input noise per chip.

\end{document}