Answer:
Using statistics!
Explanation:
If the predecessors had genetically transmitted disease,or specific features,the family tree is useful in identification and better understanding.
If a mutation occurs in the gametes it will most likely be transferred to the offspring
The second on :” the number of valence electrons stays the same” because a valence electron is the number of electrons on the outer shell of the atom and if it’s in group one then the outer shell of any element will have one electron on its outer shell
I barely understand biology :)
