The question is incomplete! There's missing the image with the red spheres.
Answer:
Number of protons = number of red spheres.
Explanation:
The atomic number (Z) is a representation of the number of protons at the nuclei of an atom, and, for a neutral atom, it also represents the number of electrons.
It's important to know the atomic number because by it the elements are organized at the periodic table, and so it's possible to identify some physical and chemical properties of the atom.
