It's B ------------------------------------
Its going to be 2.81 x 1023 atoms
Answer:
I would say A. I'm no expert, but it can't be C obviously, and I think wind would hit all of it, wearing off the top as well like the great pyramids. B would be my next choice, but A i think would be best.
This answer is 24 because 2.17 x 10 -8 is 24 so that would be your answer