Answer:
Classification system changes because the scientists find new evidence in their studies.
Explanation: The world is always changing and growing and dying as well as developing, so over time things change. For example, as you grow up do you stay the same? No, you notice the physical changes happening, well thats sort of like how the earth and its ways are always changing as well.
Renewable resources as u can guess are resources which can be reused. for example, wind energy and hydropower.
however non renewable resources are things like coal which can only be used once
Comets are most like planets have elliptical orbits
Answer:
B, lung cell, lung tissue, lung, pulmonary system
Explanation:
Lung cells are also called as pleural cells. Lung cells to form lung tissue which then forms the lung and lung and its function forms the pulmonary system. The complexity increases from cell to organ system.
Pulmonary system plays a major role in respiration. Lung cells once damaged are slow to regenerate. Alveoli are the sacs in the lungs that take up the oxygen from the inspirited air and then transfers it to the tissue.