1. The problem statement, all variables and given/known data A block with a weight of 2.9 N is at rest on a horizontal surface. A 1.3 N upward force is applied to the block by means of attached vertical string. (a) What is the magnitude of the force of the block on the horizontal surface? 2. Relevant equations I'm not sure really.. 3. The attempt at a solution I have tried solving this from several different angles. I thought to use F=2.9Nx9.81-1.3, but I believe that is incorrect.