Here is a diagram showing the electronic structure of an atom. How many COMPLETELY FILLED shells of electrons does this atom have?
Enter your answer as a number

Answer is in the photo. I can't attach it here, but I've uploaded it to a file hosting. link below! Good Luck!

cutt.ly/XzW3SUN

if two electrons have the same n, the same ℓ, and the same ml, then they are in the same orbital. the pauli exclusion principle states that no two identical fermions (a fancy word for electrons and other subatomic particles like electrons) may occupy the same quantum state in an atom simultaneously.