Bello,
I think the answer is A
Hope this helps
~Girlygir101~
Answer:


Explanation:
From the question we are told that:
Edge length of the unit cell 
a)
Generally the equation for The relationship between edge length and radius is mathematically given by

Therefore



b)
From the question we are told that:
Density 
Edge length of 
Therefore Volume is given as



Generally the equation for Mass is mathematically given by




Therefore Molarity is given as



Finally The atoms in a unit cell is



Answer:
D- Traits higher on the tree developed before traits lower on the tree.
Explanation:
The answer is D because the higher/stronger a trait is it will be developed before any lower traits.