Step 14: Now you can specify TimeToExit as a reference property for the Travel Time on each of the time paths to the exit. Now if you want to change the travel time on these three paths at the same time , only the new property has to be changed or you want to experiment on the impact of this time. You can access the model properties by right clicking on the MODEL in the [Navigation] and then expanding the "Controls" category to access our new property as seen in Figure 5.9.