7. A scientist is examining pollen grains under a microscope. The microscope uses focused beams of charged particles in a vacuum to observe the surface features of the pollen grains in great
detail. Which of the following tools is the scientist most likely using?

the most logical answer would be a

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.

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added