Answer :
Answer:
4- radioactive isotopes
Explanation:
I don't remember exactly but this question was on the regents
Uranium-238 is a non- fissile element. It is a radioactive isotope that can be best used to determine geological formations. Thus, option 4 is correct.
What are radioactive isotopes?
Radioactive isotopes are elements that have an unstable atomic nucleus and can undergo radioactive decay to produce new particles and energy. They have the same atomic number as that of their parent species.
Isobars are a substance that has atomic mass and do not include uranium. Nuclear fusion and fission are the processes of nuclear energy that combine or splits the unstable nucleus to form a new particle.
Therefore, option 4. Uranium-238 is a radioactive isotope.
Learn more about radioactive isotopes here:
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