Scientists think that algae first evolved approximately 2.7 billion years ago, and soon after this oxygen began to exist in the atmosphere. Photosynthesis by primitive plants and algae released oxygen, which gradually built up in the atmosphere.
Explanation:
Would it be <span>guitarra?
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Answer:yes they all seem correct
Explanation:
The words are in the right place
Answer:
6. Uds. son nerviosos.
7. Hoy es el nueve de octubre.
9. La mochillo es de Miguel.
10. Ud. esta contento
Explanation:
