Introduction
Recently a consultant of the Fair of Sciences sent me a message requesting the solution of a proposed subject, in college entrance exam, by FURG 2007. Here is the proposed subject:

“An adventurer plans to jump of the high of a bridge tied in an elastic (a radical sport known for ‘bungee jumping’) cable. The other extremity of the cable is tied in the bridge. In the beginning, the jumper’s movement is a free fall. Starting from the point in that the cable is stretched out, the jumper begins to slow down until a certain position, where it stops. Of this moment in before, the cable begins to pull the jumper upward. This position, where the jumper inverts the fall sense, it marks his/her largest vertical displacement D regarding the bridge. Naturally that the height of the bridge should be larger than D. it Considers a jumper’s of mass 80 kg hypothetical situation now using an elastic cable of 20 m of length. The elastic constant of the cable is 160 N/m. Calculate the value of D.
Observation: the mass of the cable can be despised in relation to the jumper’s mass. For acceleration of the gravity, use the value 10 m / s²:
The) 20 m.  B) 25 m.  C) 40 m.  D) 36 m.  And) 10 m.”