1. The problem statement, all variables and given/known data 2. Relevant equations [itex]\sigma[/itex] = F/A 3. The attempt at a solution I understand that I should evaluate the different forms of stress to find different values of the ultimate load. I also understand that I should choose the smallest value among them since anything greater than the smallest value will cause failure. I know how to calculate the normal stress in the block and the shear stress in the steel. I don't understand where shear stress occurs in the block and thus how to calculate it.