The best answer here is they show seasonal difference in flowering. if they self pollinated they could still interbreed assuming they flower in the same seasons
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.
This is true. There are a few websites online that talk about how it happens, I suggest looking them up.
