Jose, whose mass is 90 kg, has just completed his first bungee jump and is now bouncing up and down at the end of the cord. His oscillations have an initial amplitude of 9 m and a period of 4.0 s.
2. The attempt at a solution
a) The spring constant of the bungee cord is 222.0661 N/m
b) The maximum speed at which Jose is oscillating is 14.137167 m/s
c) If the damping constant due to air resistance is 6.0 kg/s, the number of oscillations which Jose makes before his amplitude has decreased to 1.0 m is 16.479
d) From what height above the lowest point did Jose jump? (in meters)
I got every other part of the question right but am having trouble figuring out part d. Do I use F=ma? Any help would be appreciated.