Water is denser than isopropanol, so the water layer will always be below the isopropanol layer if they are both in the same container. What does this tell you about the make-up of the pigments for each specimen?

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.

nucleus

would be most reasonable answer tbh

. ph changes the ability of them he enzyme to dissolve in water.