\begin{table}%t8
%\centering
\par
\caption{The chemical abundances of \hii\ regions in \sexa.  Where the
electron temperature is measured, values derived with both the CLOUDY
and the ICF methods are indicated. In the remaining cases, marked with
a "$*$'', only the determinations done with CLOUDY are listed. In
computing the average abundances, upper limits of individual
determinations are not considered.\label{Tab_c_hii_a}}
 {\footnotesize 
\begin{tabular}{lllllll} 
\hline\hline\noalign{\smallskip} 
Name   & He/H & N/H & O/H & Ne/H & S/H & Ar/H \\ 
\noalign{\smallskip} 
\hline 
\noalign{\smallskip} 
HKS2*			 &			&		 &		&		&		&	\\
CLOUDY			 &$<$0.05		& 6.1~$\pm$~0.3   &7.7~$\pm$~0.2	&6.7~$\pm$~0.2 	&6.1~$\pm$~0.2  	& 5.3~$\pm$~0.3\\ 
\hline  
HKS3			 &			&		&		&		&		&	\\
ICF			&0.05~$\pm$~0.01    	& 6.2~$\pm$~0.1   & 7.5~$\pm$~0.1   & 6.9~$\pm$~0.2   & 6.0~$\pm$~0.1   & 5.3~$\pm$~0.1\\
CLOUDY			&0.05~$\pm$~0.02    	& 6.3~$\pm$~0.3   & 7.6~$\pm$~0.2   & 6.6~$\pm$~0.3   & 6.1~$\pm$~0.2   & 5.3~$\pm$~0.3\\
Average  		&0.05~$\pm$~0.02 		& 6.2~$\pm$~0.2   & 7.5~$\pm$~0.1   & 6.7~$\pm$~0.2  	& 6.0~$\pm$~0.2  	& 5.3~$\pm$~0.2\\ 
\hline
HKS7			&			&		&		&		&		&	\\
ICF  			&0.08~$\pm$~0.01 		& 5.9~$\pm$~0.2 	& 7.2~$\pm$~0.2	& 6.4~$\pm$~0.2	& 5.9~$\pm$~0.1	& 5.1~$\pm$~0.3\\
CLOUDY  		&0.07~$\pm$~0.02   	& 6.2~$\pm$~0.3 	& 7.6~$\pm$~0.2	& 6.6~$\pm$~0.3 	& 6.0~$\pm$~0.2	& 5.4~$\pm$~0.3\\
Average  		&0.07~$\pm$~0.02   	& 6.1~$\pm$~0.3   & 7.4~$\pm$~0.2	& 6.5~$\pm$~0.2 	& 6.0~$\pm$~0.2   & 5.3~$\pm$~0.3\\  
\hline
HKS9			&			&		&		&		&		&	\\
ICF	    	 	&0.03~$\pm$~0.01  	& 6.1~$\pm$~0.2	& 7.2~$\pm$~0.2	& 6.5~$\pm$~0.2	& 5.8~$\pm$~0.1	& 5.2~$\pm$~0.3\\ 
CLOUDY	    		&0.03~$\pm$~0.02  	& 6.5~$\pm$~0.3   & 7.3~$\pm$~0.2 	& 6.5~$\pm$~0.3 	& 5.8~$\pm$~0.2	& 5.1~$\pm$~0.3\\ %OK 
Average			&0.03~$\pm$~0.02  	& 6.3~$\pm$~0.2   & 7.2~$\pm$~0.1   & 6.5~$\pm$~0.2   & 5.8~$\pm$~0.2   & 5.1~$\pm$~0.3\\  
\hline
HKS14			&			&		&		&		&		&	\\
ICF  	   		& 		  	& 6.3~$\pm$~0.2   & 7.7~$\pm$~0.1	& 7.0~$\pm$~0.2  	& 5.9~$\pm$~0.2 	& 5.2~$\pm$~0.3\\	 
CLOUDY	  	        &$<$0.05 		& 6.3~$\pm$~0.3	& 7.9~$\pm$~0.2	& 7.0~$\pm$~0.3	& 6.1~$\pm$~0.2 	& 5.2~$\pm$~0.3\\ %OK 
Average			&$<$0.05		& 6.3~$\pm$~0.3 	& 7.8~$\pm$~0.1	& 7.0~$\pm$~0.2	& 6.0~$\pm$~0.2 	& 5.2~$\pm$~0.3\\  
\hline
HKS16*			&			&		&		&		&		&	\\
CLOUDY			&$<$0.05		& 6.0~$\pm$~0.3 	& 7.7~$\pm$~0.2   & 6.4~$\pm$~0.2	& 6.0~$\pm$~0.2 	& 5.5~$\pm$~0.3\\  
\hline
HKS19*			&			&		&		&		&		&	\\
CLOUDY			& $<$0.05  		& 6.2~$\pm$~0.3   & 7.6~$\pm$~0.2   & 6.9~$\pm$~0.2	& 6.2~$\pm$~0.2   & 5.0~$\pm$~0.3\\ 
\hline
HKS23*			&			&		&		&		&		&	\\
CLOUDY			&$<$0.05		& 6.2~$\pm$~0.3 	& 7.7~$\pm$~0.2	& 6.7~$\pm$~0.2 	& 5.8~$\pm$~0.2   & 5.0~$\pm$~0.3\\  
\hline
HKS24*			&			&		&		&		&		&	\\
CLOUDY 			&$<$0.05		& 6.3~$\pm$~0.3   & 7.6~$\pm$~0.2	& 7.1~$\pm$~0.2 	& 6.3~$\pm$~0.2   & 4.7~$\pm$~0.3\\  
\noalign{\smallskip} 
\hline 
\noalign{\smallskip} 
Average values    &0.05~$\pm$~0.02&6.2~$\pm$~0.1&7.6~$\pm$~0.2&6.8~$\pm$~0.3&6.0~$\pm$~0.2&5.2~$\pm$~0.2\\
\hline 
\end{tabular}
%\\$\ddag$ Upper limits are not considered in computing the average.
} 
\par
\end{table}