None of the choices are correct
A.
Animal scientists applies principles of the biological, physical, and social sciences to the problems associated with livestock production and management.
The leg curl exercise focuses on three areas of your body: at the back of your thighs, the thing part nearest to your knee and the calves. The muscles involve in these areas are the hamstrings, quads and calf muscles, respectively.
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.