1. In which of these cases do we have enough information to say that the atom is electrically neutral?

We can say an atom is electrically neutral if both electron (for electric charge) and proton (for positive charge) have the exact same amount

Since the number are needed in some amount to be considered stable (*2-1st level - need 8 for valence level), The atom that has 7 protons and 7 electrons would be considered enough

The answer is the atom that has 7 protons and 7 electrons.