Offspring produced by an experimental cross have the following heights (cm): 10, 10, 12, 12, 14, 14, 16, 16, 18, 18. What is the mean height of the offspring

In a population that is in hardy-weinberg equilibrium, there are two possible alleles for a certain gene, a and a. if the frequency of allele a is 0.4, what fraction of the population is heterozygous? a. 0.40 b. 0.60 c. 0.16 d. 0.48