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1. A biomolecule is any molecule produced by a human organism, including proteins, lipids, and nucleic acids.

2.
a.Natural gas
b.Natural gas
c.Nuclear fission

3. Petroleum, natural gas, and also coal.

4. The source of the energy stored in biomolecules is the sun.

5. The use of automobiles has become more and more common. Also population has continued to grow, and objects are continued to be made.

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17.
a. Coal and oil
b.atmosphere and limestone
c.breathing and deforestation

18.

19.

20.