In cattle, hornless is dominant to horned, red coat color is incompletely dominant to white, where the heterzygote has a color called roan. What would the parental genotypes be in the following crosses? What would the genotypic and phenotypic ratios of the F1 be in the crosses?
a. heterozygous hornless red bull X horned roan cow
b. horned roan bull X horned whote cow
c. horned white bull X homozygous hornless red cow