1. The problem statement, all variables and given/known data The figure (Figure 1) is an incomplete momentum bar chart for a collision that lasts 15ms . Figure 1: http://session.masteringphysics.com/problemAsset/1384208/4/knight_Figure_09_06.jpg What is the magnitude of the average collision force exerted on the object? Express your answer to two significant figures and include the appropriate units. 2. Relevant equations Pix+Jx=Pfx 3. The attempt at a solution I've never seen a momentum bar chart before and we never learned anything like this in class. i tried -8N because 6-8=-2, but that was wrong How am I supposed to approach this problem?