First gap is BY USING MAGNETS
2nd is ELECTROLYSIS
3rd is EVAPORATION
On Earth it is relatively rare—5.2 ppm by volume in the atmosphere. Most terrestrial helium<span> present today is created by the natural radioactive decay of heavy radioactive elements (thorium and uranium, although there are other examples), as the alpha particles emitted by such decays consist of </span>helium<span>-4 nuclei.</span>
Answer:
positron
Explanation:
A positron is a particle produced when a proton is transformed into a neutron. Anti neutrinos are ejected from the nucleus to balance spins.
Positron emission increases the Neutron/Proton ratio. When a nuclide undergoes positron emission, the atomic number of the daughter nucleus is one unit less than that of the parent nucleus hence it is found one place before its parent in the periodic table.
