I would like help with question 2 a.b, and c for part E of project 3 in Physics. #2 is draw a force diagram for an object that has been throw and has the following components. A- on the way up. B- at the peak of its trajectory. C- on the way down.

Then for 3- Why are there two sets of equations for the use with parabolic motion? one to use with horizontal component and one set of equations to with the vertical components? thank you