true or false (a) the total energy of a system cannot change. (b) when you jump into the air, the floor does work on you increasing your mechanical energy

Total energy of a system cannot change is true.Floor doesn't do any work done.According to the conservations of the energy, energy can neither be created not be destroyed so for a system total energy needs to be constant.So the a option is true .when you jump on to the air, floor does provide support but since floor doesn't do any movement so x = 0so the work done will be zero.This is similar to the experiment that if you push to the wall, you apply force but wall doesn't move so no work done.To learn more about work done, visit herehttps://brainly.com/question/28172139#SPJ4