The table below shows the composition of four atoms. Atom! Protons! Electrons! Neutrons! Mystery Atom 1! 15! 15! 15! Mystery Atom 2! 17! 16! 15! Mystery Atom 3! 23! 23! 23! Mystery Atom 4! 23! 24! 22! Based on the information in the table, which two atoms are of the same element?