An elastic cable is to be designed for bungee jumping from a tower 130 ft high. The specifications call for the cable to be 85 ft long when un-stretched, and to stretch to a total length of 100 ft when a 600-lb weight is attached to it and dropped from the tower.

Determine
(a) The required spring constant k of the cable,
(b) How close to the ground a 186-lb man will come if he uses this cable to jump from the tower.