Which plasma lipoprotein level is most concerning when considering the risk of coronary atherosclerosis

After getting the slide and microscope ready, stella is eager to see the microscopic pond water specimen! she crouches around her microscope and aligns her eye with the microscope’s eyepiece. but she's only able to see a bright white light. at this point, no specimens or cells are visible on stella's pond water slide. after taking a moment to collect her thoughts, stella realizes she can't see any lifeforms because .

During convection, less dense fluid rises and denser fluid sinks.

Which of these is a provisioning service people get from the ocean