Can you help me please

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 .

Radiometric dating is used to tell the absolute age of materials by studying the decay rate of radioactive isotopes. the decay rates of isotopes are constant and are expressed as .

When you run, you begin to breathe heavier and faster. your heart beats more quickly, bringing more oxygen to your cells. which organ systems are working together here?