Clarify further.

chapters/annotations.tex

@@ -392,12 +392,14 @@ \section{Annotations for Simulations}\label{annotations-for-simulations}
 record Experiment
   Real StartTime(unit = "s") = 0;
   Real StopTime(unit = "s");
-  Real Interval(unit = "s");
-  Real Tolerance;
+  Real Interval(unit = "s") = $\ldots{}$;
+  Real Tolerance = $\ldots{}$;
 end Experiment;
 \end{lstlisting}
 The \lstinline!experiment! annotation defines the default start time (\lstinline!StartTime!) in {[}s{]}, the default stop time (\lstinline!StopTime!) in {[}s{]}, the suitable time resolution for the result grid (\lstinline!Interval!) in {[}s{]}, and the default relative integration tolerance (\lstinline!Tolerance!) for simulation experiments to be carried out with the model or block at hand.
 If \lstinline!StartTime! is not specified it is assumed to be \lstinline!0.0!.
+The  \lstinline!StopTime! has no default and must thus be specified.
+Tools should use appropriate defaults for \lstinline!Interval! and \lstinline!Tolerance! instead of the $\ldots{}$.
 \end{semantics}
 \end{annotationdefinition}