Question

can someone please help me with this questions .
it's urgent and needed now​

Answer 1

Explanation:

in potassium electrons and protons are 19

Neutrons are 39-19 = 20 neutrons

in sulphur electrons and protons are 16

neutrons are 32-16 = 16

Phosphorus electrons and protons are 15

neutrons are 31-15 = 16