Hi, I'm having a bit of trouble with a problem.. basically the question is as follows: A particle falling covers 64% of the entire height in its last second of the fall. What is the total height of the fall? I've tried equating two formulas, and a few other things but I can't seem to go anywhere. Any help would be appreciated. I also need clarification on something.. My teacher said that on a position-time graph, that if there is a portion that has constant velocity (ie, no curve but a straight line), that you can't have instantaneous velocity since you can't draw a tangent to a point.. but I was under the impression that instantaneous velocity was just the velocity and any given point of time? Thanks!