\begin{table}%t2
\caption{\label{Tab:obsabu}Average chemical abundances of PNe and \hii~regions in IC~10 from MG09.}
\par
%\centerline
{\small
\begin{tabular}{lllllllllllll}
\hline
\hline
\noalign{\smallskip}
                      &He/H     & O/H($\times10^{-4}$) &12+log(He/H)   & 12+log(O/H)   & 12+log(N/H)   & 12+log(S/H)   & log(N/O)       & log(S/O)\\
\hline
PNe\tablefootmark{a}  &$0.107\pm0.032$ & $2.07\pm1.30$ &$11.01\pm0.14$ & $8.22\pm0.36$ & $7.23\pm0.30$ & $6.29\pm0.22$ & $-1.08\pm0.20$ &$-2.02\pm0.40$\\
\hii~regions\tablefootmark{a} &$0.107\pm0.031$ & $2.31\pm1.59$ &$11.02\pm0.12$ & $8.28\pm0.29$ & $7.41\pm0.39$ & $6.76\pm0.31$ & $-0.87\pm0.51$ &$-1.52\pm0.23$\\
\hline
\end{tabular}}
\tablefoot{\tablefoottext{a}{Chemical abundances computed by MG09
also including upper limit electron temperature determinations.}}
\end{table}