Please help:)

important

I beleive its the middle/second option :)

Explanation:

Sorry if I'm wrong but Newton's third law is "for every action (force) in nature there is an equal and opposite reaction." meaning if object A exerts a force on object B, then object B also exerts an equal and opposite force on object A so I beleive the moon would push up on the astronaut with a force of 300 N

I hope this helps, have a good day :)

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.