Answer: When the oxygen-rich blood gets to the cells, the cells receive the oxygen and release the carbon dioxide. The blood with less oxygen and a lot of carbon dioxide returns to the heart. Then the heart returns this blood to the lungs where carbon dioxide is released and oxygen is received.
Explanation:
Biology, bio=life, logy is study
Answer:
Natural Gas
Petroleum
Coal
Explanation:
1) Ethanol is not a fossil fuel
2) 94% of ethanol is produced from the starch in corn grain
3) fossil fuel definition: a natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.
4) fossil fuels are usually found in the earth's crust... not made from corn grain
Answer: Marbles placed inside a hollow sphere are used to describe protons in a nucleus.
the marbles are not the protons nor is the hollow sphere the nucleus. Therefore, when the scientist does this, he is using a model. However the rest of the 3 options are the real things you use.
