Figure 13-2

Answer:

Initially the sample contains 100% parent material. After each half-life, half of the remaining parent material decays into daughter material: 50%/50% after 1 half-life, 25%/75% after 2, 12.5%/87.5% after 3, and 6.25%/93.75% after 4. After many half-lives, nearly all is daughter material.