1. The problem statement, all variables and given/known data I'm having problems with understanding how to use the right hand rule as it applies to forces and determining moments. If I understand correctly, The fingers point in the direction of the force, then curl in the direction of r, but I'm not sure what r would be in this case. http://imgur.com/1axaTme 2. Relevant equations M=r X F 3. The attempt at a solution My main struggle is with the force in the upper right corner. If I'm trying to find the moment about point A from this force, I point my fingers in the direction of F, then curl them in the direction of r which I'm considering to be from A to F, and I wind up with my thumb pointing into my computer screen. I'm not sure if this is correct.