\begin{table}%t3
\caption{\label{table:03}Means and RMSs of emission-line flux ratios of 
         the galaxies in the sample~A+B$^{{a}}$.}
\small%\centerline
{
\begin{tabular}{l c c c c c c}
\hline\hline
\noalign{\smallskip}
Oxygen abundance                                                    & 
log$~R_{23}$                                                         &
log$\frac{F([{\rm NII}]\lambda6584) }{F({\rm H}\alpha)}$            &
log$\frac{F([{\rm OIII}]\lambda5007)}{F([{\rm NII}]\lambda6584)}$   &
log$\frac{F([{\rm NII}]\lambda6584) }{F([{\rm OII}]\lambda3727)}$   &
log$\frac{F([{\rm NII}]\lambda6584) }{F([{\rm SII}]\lambda6720)}$   &
log$\frac{F([{\rm OIII}]\lambda5007)}{F([{\rm OII}]\lambda3727)}$  \\
\noalign{\smallskip}
\hline 
\noalign{\smallskip}
$7.05 \leq  12 +  {\rm log (O/H)}  <  7.45$ & 
     0.601  & --2.452 &  2.415  & --1.657 & --0.668 &  0.920  \\
  & (0.108) & (0.238) & (0.196) & (0.269) & (0.178) & (0.247) \\
%\noalign{\smallskip}
$7.45 \leq  12 +  {\rm log (O/H)}  <  7.55$ & 
     0.780  & --2.122 &  2.278  & --1.477 & --0.606 &  0.814  \\
  & (0.084) & (0.272) & (0.343) & (0.120) & (0.111) & (0.262) \\
%\noalign{\smallskip}
$7.55 \leq  12 +  {\rm log (O/H)}  <  7.65$ & 
     0.809  & --1.844 &  2.006  & --1.376 & --0.566 &  0.652  \\
  & (0.068) & (0.195) & (0.274) & (0.183) & (0.197) & (0.356) \\
%\noalign{\smallskip}
$7.65 \leq  12 +  {\rm log (O/H)}  <  7.75$ & 
     0.843  & --1.846 &  2.050  & --1.431 & --0.599 &  0.492  \\
  & (0.039) & (0.247) & (0.290) & (0.176) & (0.075) & (0.233) \\
%\noalign{\smallskip}
$7.75 \leq  12 +  {\rm log (O/H)}  <  7.85$ & 
     0.909  & --1.887 &  2.162  & --1.458 & --0.621 &  0.719  \\
  & (0.039) & (0.205) & (0.260) & (0.129) & (0.112) & (0.233) \\
%\noalign{\smallskip}
$7.85 \leq  12 +  {\rm log (O/H)}  <  7.95$ & 
     0.928  & --1.624 &  1.884  & --1.281 & --0.531 &  0.579  \\
  & (0.045) & (0.197) & (0.262) & (0.167) & (0.140) & (0.307) \\
%\noalign{\smallskip}
$7.95 \leq  12 +  {\rm log (O/H)}  <  8.05$ & 
     0.941  & --1.578 &  1.858  & --1.262 & --0.484 &  0.571  \\
  & (0.042) & (0.213) & (0.280) & (0.179) & (0.118) & (0.218) \\
%\noalign{\smallskip}
$8.05 \leq  12 +  {\rm log (O/H)}  <  8.15$ & 
     0.944  & --1.481 &  1.759  & --1.227 & --0.450 &  0.511  \\
  & (0.053) & (0.177) & (0.255) & (0.149) & (0.109) & (0.247) \\
%\noalign{\smallskip}
$8.15 \leq  12 +  {\rm log (O/H)}  <  8.25$ & 
     0.938  & --1.375 &  1.631  & --1.119 & --0.348 &  0.514  \\
  & (0.044) & (0.142) & (0.185) & (0.114) & (0.120) & (0.168) \\
%\noalign{\smallskip}
$8.25 \leq  12 +  {\rm log (O/H)}  <  8.35$ & 
     0.917  & --1.415 &  1.641  & --1.201 & --0.333 &  0.436  \\
  & (0.036) & (0.196) & (0.260) & (0.101) & (0.064) & (0.288) \\
%\noalign{\smallskip}
$8.35 \leq  12 +  {\rm log (O/H)}  <  8.55$ & 
     0.892  & --1.124 &  1.259  & --1.084 & --0.173 &  0.258  \\
  & (0.034) & (0.176) & (0.221) & (0.109) & (0.122) & (0.087) \\
%\noalign{\smallskip}
\hline
\end{tabular}}
\smallskip
 $^{{a}}$ Mean and RMS  of each emission-line flux ratio are given
  in the upper and lower rows. RMSs are given in parenthesis.
\end{table}