Both were powerful nations and they served as trading hubs in their respective regions during that time.
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.
Hello!
The answer would be Alveoli
In humans, oxygen and carbon dioxide are exchanged in the blood within many small sacs called alveoli in the lungs. Alveoli provide a large surface area for gas exchange.
Hope this helped!
Its an example of the predating of weaker animals.