Suppose there is a mineral body which contained some amount of superscript 238 baseline upper u, which has a half-life of 4.51 times 10 superscript 9 years, but has no lead, the end product of the radioactive decay of superscript 238 baseline upper u. if the ratio of superscript 238 baseline upper u to lead atoms today is 0.42, how long ago did the mineral body form?

How does a sample of helium at 15 degree celsius compare to a sample of helium at 215 k? a) the helium at 15 degrees celsius has a higher average kinetic energy that the sample at 215 k. b) the helium at 15 degrees celsius has lower nuclear energy that the sample at 215 k. c) the helium at 15 degrees celsius has slower- moving atoms that the sample at 215 k. d) the helium at 15 degrees celsius has smaller atoms than the sample at 215 k.