For M equals two there are two squared to four total orbitals. And that also makes sense that we have the SPSP one and PZ a total of four orbitals. For M equals three, there are nine orbitals. For M equals four, there are 16 orbitals and so on. Now, one last thing I want to mention is if we look at our periodic table what each period represents is a new energy level, a new shell level. So period number one, all the elements have a shell level of one.