Which of the following organisms have existed on Earth for the longest period of time? O single-celled organisms
O multicellular organisms
O dinosaurs
O mammals

single-celled organisms

Explanation:

cyanobacteria.. single celled organisms

1. law of superposition: when there are horizontal layers of rock. the layers at the top are the youngest.

2. law of uncomformity: where one layer is much younger than the previous one, therefore creating a gap in the time record.

3. inclusion: when there is a solid stone inside of another.

4. intrusion: a feature formed when a stone is filled with magma.

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