minor fixes

unsafe-rust/presentation.tex

@@ -57,7 +57,7 @@ Raw pointers need not respect the borrow rules...
     \emph{Fallacy 1: ``No unsafe, no bugs''}
     \begin{itemize}
         \item \emph{The ``strong'' version}: safe Rust makes bugs impossible.
-        \item \emph{The ``just concurrency'' version}: safe Rust prevents data races.
+        \item \emph{The ``just concurrency'' version}: safe Rust makes data races impossible.
         \item \emph{The ``pitch to management`` version}: safe Rust means you will never need to worry about data races.
     \end{itemize}