Answer :
Answer:
A- by finding the atomic number minus the group number.
Explanation:
You can also find the core and valence electrons by determining or looking up the election configuration of the main group elements. The atomic number is the number of protons in the nuclei of the atoms of an element. A neutral atom has the same number of electrons as protons.
Answer:
A. By finding the atomic number minus the group number
Explanation: