Answer:
The correct answer is 5s
Explanation:
Strontium atomic number = 38
Electronic configuration is 
As 
orbital is valence orbital in strontium, the outer electrons exists in that orbital only.
Parks and open spaces
hope that helps if u have any questions let me know and also if u could mark this as brainliest i would really appreciate it!
I believe its a...................
When you walk, you push against the floor, and t<span>he floor pushes back against you.
Answer: B. The floor pushes back agaisnt you.
Good luck with your studies, I hope this helps~!
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