1. The problem statement, all variables and given/known data A worker pulls horizontally on a rope that is attached to a 10 kg crate that is resting on a rough floor. The coefficients of static and kinetic friction are 0.5 and 0.3 respectively. The worker pulls with a force of 45N. What is the frictional force exerted by the surface? We did this in class and the answer was 45N but I do not understand why that is. Can someone explain?