A brown-eyed man with a heterozygous allele marries a blue-eyed woman. What color of eyes is possible in children.

Brown-eyed man – Aa (this is a heterozygote);
blue-eyed woman – aa (recessive homozygote a);
R Aa x aa (these are the parents, we cross them)
s.o. (accidental fertilization)
GA, a and a, a (these are gametes)
F1 Aa, Aa, aa, aa (this is the first offspring, that is, children)
HAP 50% recessive homozygotes, 50% heterozygotes
FAP 50% blue-eyed, 50% brown-eyed.