--- a/slides/slides08.tex	Thu Dec 03 06:37:09 2020 +0000
+++ b/slides/slides08.tex	Fri Dec 04 14:48:40 2020 +0000
@@ -803,6 +803,8 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     
 
 
+\begin{frame}<1-13>
+\end{frame}  
 
 \end{document}