Consider the following MWE.
\documentclass[addpoints]{exam}
\begin{document}
\begin{questions}
\question [10] First question text.
\question [20] Second question text.
\end{questions}
\gradetable[h]
\end{document}
I would like to add another row (say for signature of graders to individual questions) to the grade table that is generated.
How do I do that?