They are formed by natural processes like anærobic decomposition. They contain energy from ancient photosynthesis. They can literally be around 650 million years old.
A situation where friction would be desirable is rubbing your hands together to make them warm in the winter time.
<span>the young of a viviparous animal, especially of a mammal, in the early stages of development within the womb, in humans up to the end of the second month.
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The answer is B. they embody the idea of descent with modification.
Yes they are the best way to combine traits
