Answer - Well to put it in short terms.
Cells such as water cells or aquatic microorganisms need and required to have a large surface area increased. Because this helps them stay afloat without spending much amount of energy to float.
Answer:
B12 (cobalamin): Perhaps the most well-known of all the B vitamins, B12 is vital for neurological function, DNA production and red blood cell development. B12 is found naturally in animal sources like meats, eggs, seafood and dairy.
(C.) The layers of the Earth are uniform in thickness
This is untrue. The mantle is far large than the crust and there are other large size differences.