Lawrie Ryan and Roger Norris Solutions for Chapter: Electrons in Atoms, Exercise 9: Question

Use $1{\mathrm{s}}^2$ notation to give the electronic configuration for the following element vanadium having atomic number $23$.
 

Use $1{\mathrm{s}}^2$ notation to give the electronic configuration for the following element copper having atomic number $29$.
 

Use $1{\mathrm{s}}^2$ notation to give the electronic configuration for the following element selenium having atomic number $34$.