Species form of a small cells under the water when the earth was contain some alive creature in it. It's a theory.
Hope I get brainliest.
Answer:
The depth at which Drew found the algae
Explanation:
The dependent variable was the depth at which he found the algae, because that is what he measured on each day.
The independent variable was the sky conditions, since that changed from clear to cloudy, which impacted the dependent variable/the depth of the algae.
