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 addition of an extra nucleotide to a DNA sequence produces a mutation that is called insertion. An insertion mutation can be in various sizes, from one nucleotide base pair to a section of one chromosome inserted into another. When one or more nucleotides are inserted into the genome, the processes of translation and transcription could be disrupted, resulting in altered protein synthesis.
In co dominance, both alleles show. Thus, the filial, F1, generation, will most likely be white with red spots/speckles. See image below.
A) is your best answer.
Relative Dating gives the 'relative dating', which allows one to find the difference of age between many different of fossils. However, radioactive dating is used to get a more exact measurement of a fossil, but it can only be used for certain types of fossils.
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