For the first one, electrons travel around the nucleus in fixed energy levels with varying energies.
Second one, protons, neutrons, and electrons have a mass, but electrons have far less mass
Third one, cations and protons
Fourth, not sure.
Natural selection is where positive traits survive more, allowing those to become more common. Mutation is where radioactivity changes genes in a random way. Natural selection allows positive mutation to become more common. Adaptation is where natural selection works for a species specifically more a new habitat.
True
Entrainment is to synchronize an organism to an external whole for example music or tapping.
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Answer:
The Earth is 4.6 Billion years old.
QUESTION 2:
Option A is the correct answer.
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