John can roll his tongue and is heterozygous for this dominant trait (rr). john’s second toe is shorter than his first. his wife rita cannot roll her tongue and has a longer second toe. rita is heterozygous for this dominant trait (tt). use a punnett square to predict the possible genotype(s) and phenotype(s) of their first child?

       rT       rt

Rt    RrTt     Rrtt

rt     rrtt        rrtt

25% chances for the genotype to be heterozygous roll tongue and heterozygous longer second toe.

25% chances for the genotype to be heterozygous roll tongue and homozygous short toe.

50% chances for the genotype to be  homozygous recessive no roll tongue and homozygous recessive short toe.

Phenotypes would be 25% tongue roll with longer toe. 25% tongue roll with shorter toe. 50% no tongue roll,shorter toe.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."