1. For a neutral atom containing Z electrons estimate the velocities of the electrons of (i) inner and (ii) outer shells. Make your own judgment regarding what the velocities might depend upon. Assume that all fundamental constants you might need are at your disposal, and that the problem is non-relativistic. Based on your result (iii) estimate the value of Z at which relativistic effects start entering the physics (the answer to this last question should have the form Z = number composed of parameters of the problem such as Planck's constant, electron charge, speed of light etc.).