You are an engineer getting ready to go meet the mayor on the new building development project going on downtown. The mayor has concerns that the building has been built a lot taller than what it was supposed to be. As you stand on top of the building with the mayor, you realize that you forgot your tape measure (but you do have your cell phone). Using just your cell phone and your knowledge of kinematics equations (and maybe a nearby rock), you must impress the mayor with how smart you are and reassure him the building is the proper height. Explain how you could use your cell phone and a specific kinematic equation to estimate the height of the building.