Are you looking for projects like experiments?
Answer :<em> That trough time, a specie of animal, plant, bacteria can change.
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<em>When a life form reproduces, one of its"babies" may be different from its parents because of genetic mutation. </em>
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I'm guessing the answer is a
the radiations that are used to treat cancers are of the gamma type. primarily emitted from cobalt-60 (a radioactive isotope). and it is more controlled than other radiation exposures. i.e. solar radiation which is not controlled.
hope that this helps.