Add question about differences of pairs and lists

VL1.tex

@@ -688,6 +688,7 @@ For haskell IDEs, see \url{https://wiki.haskell.org/IDEs}
 \item What does the output of a haskell function depend on?
 \item What is laziness?
 \item When are types checked in haskell?
+\item What are the differences between lists and pairs?
 \end{itemize}
 \vspace{\baselineskip}
 Does this compile? If not, fix it. Is this a total function?