It's the last one. They all have the same number of electrons in their outer ring. They're also called valence electrons.
Hope this helped!
Its a snake. snakes have lungs and a foot but no legs. its offspring are in eggs
For Number 1, the rate changes multiple times. Some times it goes up .4 and sometimes it remains the same. I think you may need to check you work to get a more fluent flow for rate of change.