#3) A hiker is climbing up a mountain at a constant rate. At 9 AM they have traveled 3.5 miles. By 10 AM they have traveled 5.2 miles. Write a model and determine how long the hiker would
have traveled by 11:45 AM.

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.