Humans vary in their ability to taste the bitter chemical compound phenylthiocarbamide ( PTC ). The taster phenotype is dominant to the non-taster phenotype. Researchers tested the PTC taster phenotype of individuals from an isolated population. In the sample, 780 individuals were able to taste PTC and 70 individuals were not able to taste PTC .Assuming the population is in Hardy-Weinberg equilibrium, what is the frequency of the non-taster allele