1. The problem statement, all variables and given/known data A block of mass M=3.4 kg is dragged over a horizontal surface by a force F=20.0 N. The block is displaced a distance d=17.0 m, the friction force Ff is 3.3 N. What is the work done by the friction force? 2. Relevant equations Ff=μkFn 3. The attempt at a solution I solved a problem before this one in finding the applied force but this one is very confusing to me. I have no idea where to even start. Thank you!