Respuesta :

AMIM14

Answer:

2- Helium(He)

20-Calcium(Ca)

Answer:

Do you mean under 2 & 18 or under 4 & 20?

Explanation:

2 & 20 are in opposite sections of the periodic table. If you mean 2& 18 the element is Krypton or if you mean 4 & 20 the element is Strontium