Which 2 systems work to deliver oxygrn to cells

Many farmers prefer cattle without horns because it is safer for their herds. the allele for no horns (n) is dominant to the allele for the presence of horns (n). a farmer mates a male with horns to a heterozygous female without horns. what is the chance that the offspring will have horns?

Which is one example of a phenotypic change that is not genetic

Which animal is a producer in this ecosystem