If this population continued for the next 100 years with no changes in arm length, what could you say about these sea stars?

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

phaneritic textures in which phaner means visible so phaneritic textures are standard of impertinent volcanic rocks. these rocks crystallized gradually under the surface of earth. when the magma cools deliberately then the ores have chance to develop and produce long crystals.