ABO blood groups in human population is controlled by three different alleles of the gene (I). How many genotypes and phenotypes respectively could exist in human population with respect to this?

Human blood group is controlled by 3 alleles i.e. IA, IB and i.6 types of possible genotypes are IAIA, IBIB, IAIB, IAi, IBi and ii.The genotypes IAIA  and IAi  reflect the  phenotype A blood groupThe genotypes IBIB and IBi  reflect the phenotype B blood groupThe genotype IAIB for the phenotype  AB blood groupThe genotype ii for the phenotype O blood group.