So I got the correct answers for this question but I don't understand how. I don't understand the breakdown of the components. I don't understand where what variables should be. 1. The problem statement, all variables and given/known data A rock is projected at a cliff with initial speed of 42m/s, at 60deg above the horizontal. It strikes A at 5.5s. Find the height of the cliff (I labeled it as dy but don't know if thats the same thing). Find the speed before impact at A. Find the max height reached (H). 3. The attempt at a solution Attached. Why is gravity negative? Why do we find dy instead of H and how did this happen? Is there no acceleration in the x direction at max height? So a=0? That's the only way it works out. Why doesn't my first solution for c) work? I don't understand the concept behind this problem at all.