What evidence places fish as the first vertebrates

If the coding part of an mrna molecule is 1800 nucleotides (bases) in length, this molecule will contain codons and code for a polypeptide that is amino acids long.

Aparent with freckles is crossed with a parent without freckles. the punnett square shows the possible genotypes and phenotypes of the offspring. which statement accurately describes the probability of phenotypes? a. the offspring are more likely to have freckles. b. the offspring are more likely to have no freckles. c. the likelihood of the offspring having freckles and not having freckles is the same. d. the likelihood of the offspring having freckles and not having freckles cannot be determined.

What if the yeast were extremely active and produced more than 100ml gas. would you know? why/why not