I'm using LuaLaTex to make my slide. There is a table in my slide. However, i can't control the size and some parts of the table can't be vievew. How can I solve this issue?
\documentclass[11pt]{beamer}
\begin{document}
\begin{frame}{Plan for completion and thesis submission}
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\begin{center}
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\begin{tabular}{|l|c|c|c|c|c|}
\hline
\centering{Tasks} & \multicolumn{2}{|c|}{\small{2016/2017}} & \multicolumn{2}{|c|}{\small{2017/2018}} & \small{2018/2019}\\
\cline{2-6}
& \tiny{Sem. 1} & \tiny{Sem. 2} & \tiny{Sem. 1} & \tiny{Sem. 2} & \tiny{Sep - Dec 18} \\
\hline
\small{Reading and understanding} & $\times$ & $\times$ & & &\\
\small{of various advanced concepts} & & & & &\\
\small{on groups and graphs} & & & & &\\
\hline
\small{Write a literature review} & $\times$ & & & &\\
\hline
\small{Obtain examples (by hand} & & $\times$ & & &\\
\small{or using a computational} & & & & &\\
\small{algebra system)} & & & & &\\
\hline
\small{Form conjectures and} & & $\times$ & & &\\
\small{prove or disprove the} & & & & &\\
\small{conjectures} & & & & &\\
\hline
\small{Work on} & & $\times$ &$\times$ & $\times$ & $\times$\\
\small{research problems} & & & & &\\
\hline
\small{Submit a paper to an} & & & $\times$ & &\\
\small{ISI-indexed journal for} & & & & &\\
\small{publication} & & & & &\\
\hline
\small{Write up thesis for} & & & &$\times$ &\\
\small{submission} & & & & &\\
\hline
\small{Complete writing up} & & & & & $\times$ \\
\small{of thesis and submit} & & & & &\\
\small{thesis by December 2018} & & & & &\\
\hline
\end{tabular}
\end{center}
\end{frame}
\end{document}
