Answer:
D. the answer is triangular
<span>the intellectual and practical activity encompassing the systematic study of the structure and behavior of the physical and natural world through observation and experiment.
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Answer is Middle Paleozoic era.
Paleozoic era was in 542 Ma - 245 Ma and it has 6 periods as Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian.
360-280 Ma - forming of vascular plants with woody tissues, seeds and veins.
430 - 410 Ma - forming of jawed fishes and first amphibians.
420 Ma - forming of scorpions
360 Ma - forming of crustaceans.
The answer is D) evolving
The answer is A) a patient that can receive o- o+ b- and b+ is b+