The half-lives for the radioactive decay of various elements are listed in the table below. Parent Isotope Daughter Isotope Half life
Carbon-14 Nitrogen-14 5,730
Uranium-235 Lead-207 710 million
Potassium-40 Argon-40 1.25 billion

Required:
a. Suppose you discovered a meteorite that contains a small amount of potassium-40 and its decay product argon-40. You determine that 1/8 of the original potassium-40 remains; the other 7/8 has decayed into argon-40. How old is the meteorite?
b. A piece of cloth was painted with organic dye 40,110 years ago. What percentage of the original carbon-14 in the organic dye remains after all this time?
c. The oldest minerals found on Earth are zircons. One isotope used to measure their age is uranium-235. A single crystal contained 200 nanograms of uranium-235 when it first formed. How much uranium-235 does the crystal still contain if it formed 4.26 billion years ago?
d. Is radiocarbon dating a useful tool for determining the age of the solar system? Explain why or why not