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\begin{document}
We can describe atoms through use of the Schr\"{o}dinger
equation which is given as
\begin{equation}
\label{schro}
E\Psi=\textbf{H}\Psi.
\end{equation}
If we carry out equation \ref{schro} to its fullest consequences,
we can describe figure \ref{fig:Atoms}.
\begin{figure}
\centering
\begin{subfigure}{.45\textwidth}
\centering
\includegraphics[width=\textwidth]{atom.png}
\caption{Big atoms}
\label{subfig:big}
\end{subfigure}
%%%%%%%%%%%%%%
\begin{subfigure}{.45\textwidth}
\centering
\includegraphics[scale=.25]{atom.png}
\caption{Small atom}
\label{subfig:small}
\end{subfigure}
\caption{Atoms}
\label{fig:Atoms}
\end{figure}
We also can use this to describe the atomic masses of
elements from big, \ref{subfig:big}, to small, \ref{subfig:small}.
Some of these masses are given in table \ref{tab:atommass}.
\begin{table}[H]
\centering
\begin{tabular}{c|c}
Element&Atomic Mass (amu)\\\hline
H&1.007 825 032 07(10\\
He&3.016 029 3191(26)\\
Li&6.015 122 795(16)\\
Be&9.012 182 2(4)\\
B&10.012 937 0(4)\\
C&12.000 000 0(0)
\end{tabular}
\caption{Atomic Masses}
\label{tab:atommass}
\end{table}
We don't have a \ref{noref}
\end{document}