The abo blood group is transmitted in humans as follows: the a and b alleles are dominant to the o allele but codominant with each other. the o phenotype (oo genotype) is known as the "universal donor" in smallvolume blood transfusions, whereas the ab phenotype (ab genotype) can be considered a "universal recipient". a certain human population is at hardy-weinberg equilibrium with respect to blood type, with allele frequencies a = 0.5, b = 0.2, o = 0.3. in this population(fill in the blanks), universal donors occur at a frequency of whereas universal recipients occur at a frequency of . 0.25; 0.30b. 0.09; 0.20c. 0.3; 0.7d. 0.06; 0.04e. 0.15; 0.10