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Science Test study
| Question | Answer |
|---|---|
| What are the substance in earth's second atmosphere? | Water vapor, nitrogen and carbon dioxide |
| What are the substances in the first atmosphere? | Helium and hydrogen |
| What substance do living organisms give to the atmoshpere? | Oxegyn |
| What are the earliest life forms similar to? | Bacteria |
| What is a comet? | A ball of dust and ice that orbits the sun |
| What galaxy is earth in? | The Milky Way |
| What is the closest galaxy to the Milky Way? | The Andromeda Galaxy |
| What is the closest star to earth besides the sun? | Proxima Centuri which is 4.2 light years away |
| What is the distance a star travels in a year? | Light years |
| When did Precambrian begin? | 4.6 billion years ago |
| When did accretion start? | 4.6 billion years ago |
| Order of earth's formation: | 1. Beginning of accretion-4.6 billion BP, 2. End of accretion- 4.5 billion BP, 3. Precambrian-544 million BP, and 4. Modern time |
| When did Cambrian start? | 544 million years BP |