How to find genotype and phenotype?

Genotype is one's actual genetic information, regardless of dominance. Phenotype is the actual external expression of this genetic information. So uming that T is a dominant trait and t is its paired recessive, Bill's genotype is Tt, the data, and his phenotype is T, while Don also has a phenotype of T, his genotype is TT. The large T dominates the small t in Bill's case, and only the T is expressed, while the small t has potential to be ped on to offspring.