Robuta

https://www.ebi.ac.uk/chebi/CHEBI:30219 helium-4 atom (CHEBI:30219) The stable isotope of helium with relative atomic mass 4.002603. The most abundant (99.99 atom percent) isotope of naturally occurring helium. helium 4atomchebi https://www.merriam-webster.com/dictionary/helium-4 HELIUM-4 Definition & Meaning - Merriam-Webster The meaning of HELIUM-4 is helium. helium 4definitionmeaningmerriamwebster