Heterozygotes make up 20% of the population.Homozygotes make up 80% of the population.In the entire cat population, 60% of the alleles are TS.In the entire cat population, the frequency of the TL allele is 0.4.Assuming random mating, each gamete has a 40% chance of having a TL allele and a 60% chance of having a TS allele.
The gene pool for tail length in the population is composed of alleles TL and Alleles TS .The allele frequency of TL is 0.4 (160/400). Another way to express this is that 40% of the alleles are TL .The allele frequency of Ts is 0.6 (240/400). Another way to express this is that 60% of the alleles are Ts .Therefore, each of the gamete either the sperm or the egg has a 40% chance of carrying allele TL and a 60% chance of carrying allele Ts, assuming mating is random.