Which of the foldwing is the most important in determining how quickly materials can move into and out of a cell? (A) the volume of the cell (B) the mass of the cell (C) the surface area of the cell (D) the location
of the cell in relation to its environment.

b the mass of the cell

Explanation:

this protocol describes a detailed procedure for intracellular flow cytometry staining.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.