3} In the Empire State Building Run up, Competitors race up the 1515 steps of the empire state building climbing a total vertical distance of 320 m. How much gravitational potential energy does a YDKg racer gain during this race? 4} The maximum energy a bone can absorb without breaking is surprisingly small. For a healthy human of mass 60 Kg [132 pounds], experiments show that the leg bone can absorb about ZUUJ. For what maximum height could a person jump and land upright on both feet without breaking their legs? Assume that all energy is absorbed in leg bones on a rapid landing