(Solved): please help  5. After 62.0 hours, 1.0 gram remained unchanged from a sample of 42K (half-life i ...

5. After 62.0 hours, 1.0 gram remained unchanged from a sample of 42K (half-life is 12.4 hours). What was the mass of b 42K in the original sample? A. 64 grams B. 32 grams C. 16 grams D. 8 grams E. 4 grams 6. The energy released by the detonation of an atomic bomb is NOT related to A. fission of the atom's nucleus B. fusion of the atom's nucleus C. a chain reaction D. the release of many neutrons E. the uncontrolled speed of many neutrons 7. The joining of many hydrogen nuclei in the nuclear reaction that occurs in stars is called a A. mass defect B. sunburn C. fusion reaction D. fission reaction E. helium reaction