Respuesta :
if the atomic number is 20, this means the element is Calcium (Ca).
the electron configuration of Ca is:
[Ca]= [tex]1s^22s^22p^63s^23p^64s^2[/tex]
the electron configuration of Ca is:
[Ca]= [tex]1s^22s^22p^63s^23p^64s^2[/tex]
Answer: D
Explanation: The correct answer is option D for Plato users