Given that the 5 kW system would cost $20,000 to install (minus a 30% federal tax credit), how many years would it take to recoup the initial investment? To investigate the relationship between the coefficient of friction and the braking distance, you need to hold the other variables fixed. Let G = 0.02. Which of the following is a correct interpretation of the value G= 0.02? Given that the 5 kW system would cost $20,000 to install (minus a 30% federal tax credit), how many years would it take to recoup the initial investment? To investigate the relationship between the coefficient of friction and the braking distance, you need to hold the other variables fixed. Let G = 0.02. Which of the following is a correct interpretation of the value G= 0.02