1. The problem statement, all variables and given/known data Plutonium 239 (P-239) decays at a rate of 0.00284 percent per year. If the initial sample size of P-239 is 10 g, how much will remain as P-239 after 20,000 years? 2. Relevant equations A=A0e^-rt 3. The attempt at a solution A=10e^-0.00284*20000 lnA=ln10+lne^-56.4 lnA=1-56.4 A=8.7*10^-25 This answer doesn't seem reasonable and I don't have confidence that I did everything correctly.