Coal and oil.... Fossil fuel is formed from decaying plants/animals who were buried and eventually converted to crude oil, gas by the exposure to heat and the pressure of the earths crust. This takes about 1 million years to happen.
The presence of helium gas indicates the radioactive sample is most likely decaying by α-decay, or alpha decay. α-decay is the type of radioactive decay in which an atomic nucleus emits α particles. α particles are Helium nuclei. So the correct answer would be α-decay.
Answer:
The answer of this is question is A.