Upon opening the document, it should look something like the screenshot below. You should be able
to modify the position, velocity and acceleration of the car by simply placing your mouse into those
areas and entering a number. Pressing the start button will get the simulation going.
However, if your simulation window appears zoomed in and looks more like this (see figure below),
then with your mouse, right click on the simulation and select show all. Then press the F11 key (for
Windows system) to view the entire simulation on the screen.