Continental drift happened around the Jurassic period, 175 million years ago.
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A: Population
If a group of one certain species are living in the same area they are a population. The same goes for humans, we are the same species and when we live in the same area we say we are part of a population. That’s why you would hear things like “the population of massachusetts is 2million” or whatever it is.
The object's mass. Weight would be how gravity affected it, size is how large it is, density is how tightly the molecules are to each other. Mass is how much matter is in the object.
Answer: Over 4 billion years ago
Explanation: The chemical reactions between carbon and water is said to bring about life according to scientists. These reactions builds largely upon four families of chemicals (lipids, carbohydrates, amino acids, and nucleic acids).
However, the actual time of life on Earth has varying speculations from different scientists in fields of study (such as molecular biology, chemistry, oceanography, etc).
Furthermore, microfossils within hydrothermal-vent precipitates dated from 3.77 to 4.28 billion years is presumed to inhabit the oldest record of life on Earth. Hence, which is presumed to have occurred after ocean formation 4.4billion years ago.
Thus, the actual date of the chemical reactions that brought about life is not rigid, but presumed to have occurred over 4billion years ago (according to research).