A fire fighter of mass 80 kg slides down a vertical pole with an acceleration of 4 m/s^2. What is the magnitude of friction force acting on the fire fighter? A. 480 N B. 1120 N C. 800 N C. 320 N Show all work and all steps: 1. Type the given information and assign a variable for each known value. 2. Type the general equations that you will use to solve the problem using the variables (no numbers yet) 3. Use the given values with units to obtain the final