Need help with this lab please. I don't really understand how to run the simulation and how to start answering questions.

Simulation link is here for reference:

http://phet.colorado.edu/en/simulation/forces-and-motion-basics

PhET Friction Lab The Purpose of this lab is to determine frictional forces on an object based on computer simulations as well as solve for unknown forces and masses using the equations learned in the class. For this lab simulation you will use the PhET simulation from the following link: het.colorado.edu en simulation forces-andmotion-basics Run the simulation and click on the Friction tab on the top of the sim. While on the friction tab select the following settings, DO NOT MOVE THE FRICTION SLIDER >>> With the settings now currently in place you will complete the following chart by manipulating the simulation. Play with it for a few moments to familiarize yourself with the controls.Use the following equations: Ff = u Fn Fg = mg Trash Can Apped Force Object(s) 2x Crates What has to happen before the Applied Force begins to move the box? What happens once you exceed the frictional forces? Explain what happens to the box once you stop applying force? Now we will manipulate the settings and INCREASE the amount of Friction to anywhere on the slide - it must move. Object(s) Trash Can Refrigerator Based on the simulation, explain how you were able to solve for the weight of the present include variables and equations in your answer. There is error with the simulation, when the box began moving, what should have happened in regards to friction? Explain your answer in terms of forces and coefficients