\begin{table}%T2 \par \caption{\label{tab:ampli}Amplification factors determined from the (D,~AB) pair.} \small%\centering \par \begin{tabular}{lcccc} \hline\hline \noalign{\smallskip} Lines & Date & $A$ & $M$ & $\mu$\\ \hline \ion{Si}{iv}-\ion{C}{iv} & 1989 & 0.645 $\pm$ 0.015 & 0.390 $\pm$ 0.020 & 1.65 $\pm$ 0.12 \\ \ion{Si}{iv}-\ion{C}{iv} & 1993 & 0.915 $\pm$ 0.015 & 0.460 $\pm$ 0.040 & 1.99 $\pm$ 0.21 \\ \ion{Si}{iv}-\ion{C}{iv} & 2000 & 0.775 $\pm$ 0.010 & 0.400 $\pm$ 0.020 & 1.94 $\pm$ 0.12 \\ \ion{Si}{iv}-\ion{C}{iv} & 2005 & 0.775 $\pm$ 0.010 & 0.400 $\pm$ 0.040 & 1.94 $\pm$ 0.22 \\ Ly$\alpha$-\ion{N}{v} & 1994 & 1.050 $\pm$ 0.025 & 0.460 $\pm$ 0.030 & 2.28 $\pm$ 0.20 \\ Ly$\alpha$-\ion{N}{v} & 2000 & 0.805 $\pm$ 0.015 & 0.430 $\pm$ 0.030 & 1.87 $\pm$ 0.17 \\ H$\beta$-[\ion{O}{iii}] & 2005 & 0.630 $\pm$ 0.010 & 0.425 $\pm$ 0.015 & 1.48 $\pm$ 0.08 \\ H$\alpha$ & 2005 & 0.540 $\pm$ 0.015 & 0.395 $\pm$ 0.015 & 1.37 $\pm$ 0.09 \\ \hline \end{tabular} \end{table}