\begin{table}%t5
\par
\caption{\label{tab_mod_range}{Range of model parameters for ``exact'' solutions.}}
\par
%\begin{centering}
\begin{tabular}{lccccc}
\hline\hline
\noalign{\vskip3pt}
Parameter            &        \multicolumn{4}{c}{}                & 1-$\sigma$ box \\
\hline\\[-3mm]
$R_{{\rm in}}$ (10$^{17}$~cm) & 1.0 &  1.0    &    1.0   &    1.4     &      --     \\
$N_{{\rm in}}$(H) (\cmt) &    900  &   1200    &   1600   &   1200     &      --     \\
\tbb\ (kK)           & 127~$\pm$~5 & 135~$\pm$~7  & 145~$\pm$~3 & 135~$\pm$~7  & 135~$\pm$~10 \\
\teff\ (kK)          & 112~$\pm$~5 & 120~$\pm$~7  & 130~$\pm$~3 & 120~$\pm$~7  & 120~$\pm$~10 \\
$L$ (10$^{36}$~erg~s$^{-1}$) & 11.~$\pm$~.1 & 10.~$\pm$~.1 & 9.~$\pm$~.1 & 11.~$\pm$~.1 & 10.~$\pm$~1. \\
He/H~$\times$~10$^{3}$ & 108~$\pm$~0 & 108~$\pm$~0  & 109~$\pm$~1 & 108~$\pm$~0  & 108~$\pm$~1  \\
C/H~$\times$~10$^{6}$  & 197~$\pm$~1 & 212~$\pm$~4  & 230~$\pm$~4 & 222~$\pm$~4  & 214~$\pm$~17 \\
O/H$\times$~10$^{6}$  & 165~$\pm$~7 & 172~$\pm$~9  & 178~$\pm$~4 & 169~$\pm$~9  & 170~$\pm$~12 \\
N/O~$\times$~10$^{3}$  & 149~$\pm$~4 & 147~$\pm$~1  & 150~$\pm$~1 & 147~$\pm$~1  & 149~$\pm$~3  \\
Ne/O~$\times$~10$^{3}$ & 142~$\pm$~3 & 143~$\pm$~1  & 153~$\pm$~2 & 149~$\pm$~1  & 145~$\pm$~5  \\
Ar/O~$\times$~10$^{5}$ & 232~$\pm$~6 & 228~$\pm$~5  & 226~$\pm$~2 & 228~$\pm$~5  & 230~$\pm$~7 \\
\hline
\end{tabular}%\par\end{centering}
%\begin{list}{}{}
\par
%\begin{description}
%\item [{$^{{\rm a}}$}]
%\end{list}
\par
%\end{description}
\par
\end{table}