How do scientists think that the invasive lionfish made their way into the Atlantic ocean, where they have no natural predators? a They swam into their new habitat. b They were released to control another invasive species. c They were released to provide a new species for fisherman to catch. d They were released by pet owners into the ocean

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.