Which of the following is an example of geographic isolation?

A. a population of salmon dies out because they cannot find food.
B. a zebra with a long mane moves into a population of zebras with short manes.
C. a population of squirrels is separated by a mountain range and cannot interbreed.
D. two populations of rabbits are forced together after a flood.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

1.43 x 10^-11 j the guy commented the awnser just making sure u see it .