Answer: C. there is more silicon than calcium at the surface of the earth
Explanation:
Answer:
Circulatory would be the answer.
Explanation:
Red blood cell is shaped as a biconcave discs, this shape allows them to squeeze through small capillaries.
The biconcave shape of the cell allows oxygen exchange at a constant rate over the largest possible area. The biconcave shape increases the cell's surface area compared to a flat disk of the same size. The greater surface area makes it easier for gases to move into and out of the red blood cell.
The biconcave shape provides a large surface area compared to the volume of the red blood cell, allowing diffusion to happen efficiently. This shape optimizes the ratio of surface area to volume, facilitating gas exchange. It also enables them to fold up as they move through narrow blood vessels.
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B. Absolute dating uses the half-life of an element
Absolute dating is a technique that uses radioactive minerals present in rocks and fossils while relative dating compare the sample in terms of age difference. However, absolute dating is more accurate because it uses half-life of an element and provides dates in years.
Tertiary consumer because you have no predators trying to eat you. You are at the top of the food web
