Please help with the questions

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?

What noticeable trend from this graph might be used to make a conclusion?

Give an example of a trait that is controlled by more than one gene.