I think burgess shells would be the answer
Answer: Potassium-40 decays into argon gas over time.
Explanation: Potassium-argon dating is a dating method used to determine the age of sedimentary rocks by comparing the proportion of K-40 to Ar-40 in a sample of rock, and knowing the decay rate of K-40.
Potassium-40 undergoes decay following first order kinetics as given below:

Answer:Bb
Explanation:
Homozygous gene pair are pair of allele that are identical e.g BB
Heterozygous gene pair are pair of allele that are not identical e.g Bb
Heterozygous gene pair could show complete dominance where the Allele for dominant will completely mask the effect of the reccessive allele and the individual will express the trait of the dominant allele.
Its a 50/50 so two of there kids will have blue eyes and two will be brown eyes but the children with brown eyes with be heterozygous for blue eyes and same thing with the brown eye children