Energy stored by a restoring force and energy density of the stretched material(mathematical only and state each term respectively)

This is the answer of your question

Shy diving is the only sport which doesnot require a high level of physical fitness

The answer is 4f======since electrostatic force is given by    we let f be the electrostatic force when  r = 1 m    if we let  denote the electrostatic force when the distance is decreased so that r = 0.5m, then    we established earlier that f = kq₁q₂. therefore    the force will now be 4f.