Trey is conducting an experiment to determine which fish food causes the most goldfish activity over a period of two weeks. he is going to set up ten fish tanks with 4 goldfish each. he will feed the fish in half of the tanks swift salmon food and the fish in the other half of the tanks fast flounder food. he will expose them to direct sunlight for 4 hours per day. each tank will have the same size and type of goldfish, which will be fed the same amount of fish food. each tank will be filled with the same type and amount of water and with the same type and amount of river rock.

i don't think the actual question was made clear in the text. would you be able to rewrite it but including the question? i could see if i can you then : )

bacteria that live on the ocean floor are sustained by phytoplankton. phytoplankton, microscopic marine photosynthetic organisms, have a vastly significant role to play not only in the marine food web of which they’re part of, but also on a more global scale. despite their infinitely small size in comparison to other marine organisms, these tiny creatures occupy an immensely important ecological niche: they are the foundation of the marine food web, and as primary producers, play key roles in supporting all other organisms in the marine environment, as well as in the regulation of the earth’s climate through the sequestration of carbon, oxygen production, and other related processes. phytoplankton account for roughly half of all global primary productivity; therefore, their significance extends far beyond the marine environment alone. there is an intriguing sense of irony in the realization that these tiny living beings that often live out their existence unnoticed and undetected by the rest of the world, have such a far-reaching impact on the lives of virtually all other living organisms on the planet, particularly on those in the marine environment. the world that we have become accustomed to has been and is continuously shaped by the workings of these miniscule yet vital “plants of the sea”.

hope this !