Answer:
one that has an unstable nucleus
Explanation:
An isotope is defined as a chemical variant present in an atom with different number of neutron but same number of protons.
Radioactive decay is the sudden breakdown of an atomic nucleus allowing matter and radiation to be emitted from the nucleus. A radioisotope with unstable nuclei undergoes radioactive decay because they do not have adequate binding energy to keep the nucleus together. there are four types of Alpha, Beta, Gamma Decay and Positron Emission.
Hence, the correct option is "one that has an unstable nucleus"
Is it first?
Explanation:
Darwin first major break through was finding natural selection by using the pea pod method and noticing how some were yellow and some were green with different textures.
Portland, Oregon, is a city right next to northern west coast of the USA. Besides being very close to the sea, it is also laid on a river. The sun that heats up the ocean and the river leads to evaporation, causing water vapour to ascend, because of a few wind currents, this water vapour is taken to Portland's area where it colds down and condensates, raining over Portland.
NO cLuE I jUsT nEeD pOiNtS tO bEaT mY liTtLe bRoThEr
