first of all there is only two types of selective breeding and they are hybridization and inbreeding.
1: True
2: True
3: False
4: False
(Question 2 might not be true, not sure)
Answer: they all have 7 electrons they have different atom sizes
Explanation: hope it helps
Electrons are extremely small. Atoms are comprised mostly of empty space. Protons have a positive charge.
Hope this helps.