(ENVIRONMENTAL SCIENCE)You are probably familiar with titles that historians have given to specific periods in history such as Pax Romana, the Renaissance, and the Victorian Era. What title would you give to each of the three periods of U. S. environmental policy discussed in

this lesson? Explain your choices.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.