\begin{table}%t3
%\centering
\par
\caption{Helium abundance \label{tab5}}
\begin{tabular}{lc} \hline\hline
Parameter                           & Value \\ \hline
$T_{\rm e}$(O {\sc iii}), K               &20~180   \\
$T_{\rm e}$(He$^+$), K                    &20~010   \\
$N_{\rm e}$(He$^+$), cm$^{-3}$            &295     \\
{\it EW}$_{\rm abs}$($\lambda$4471), \AA      &0.4     \\
{\it EW}$_{\rm abs}$($\lambda$3889)/{\it EW}$_{\rm abs}$($\lambda$4471)      &1.0     \\
{\it EW}$_{\rm abs}$($\lambda$5876)/{\it EW}$_{\rm abs}$($\lambda$4471)      &0.3     \\
{\it EW}$_{\rm abs}$($\lambda$6678)/{\it EW}$_{\rm abs}$($\lambda$4471)      &0.1     \\
{\it EW}$_{\rm abs}$($\lambda$7065)/{\it EW}$_{\rm abs}$($\lambda$4471)      &0.1     \\
$\tau$($\lambda$3889)   &2.9 \\
$\Delta$$I_{\rm coll}$(H$\alpha$)/$I$(H$\alpha$), \% &4.95 \\
$\chi^2_{\rm min}$          &0.1825 \\
$y^+$($\lambda$3889)    &$0.0782\pm0.0134$ \\
$y^+$($\lambda$4471)    &$0.0802\pm0.0032$ \\
$y^+$($\lambda$5876)    &$0.0788\pm0.0012$ \\
$y^+$($\lambda$6678)    &$0.0787\pm0.0018$ \\
$y^+$($\lambda$7065)    &$0.0789\pm0.0018$ \\
$y^+$(weighted mean)    &$0.0789\pm0.0010$ \\
$y^{++}$($\lambda$4686) &$0.0034\pm0.0002$ \\
$ICF$(He)               &0.993             \\
$y$(weighted mean)      &$0.0817\pm0.0010$ \\
$Y$(weighted mean)      &$0.2463\pm0.0030$ \\
\hline
\end{tabular}
\end{table}