In the United States about 16% of the population is Rh negative. The allele for Rh negative is recessive to the allele for Rh positive. If the student population of a high school in the U.S. is 3,000, how many students would you expect for each of the three possible genotypes?

In certain African countries, 4% of newborn babies have sickle-cell anemia, which is a recessive trait. Out of a random population of 10,000 newborn babies, how many would you expect for each of the three possible genotypes?
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