Throughout history, people have been studying the living and nonliving world. what is the name of the formal procedure scientists use to study the world around them?

The correct answer will be scientific method.

Explanation:

The scientific method is a step by step process used by scientists to study the world around them.  

The scientific method or protocol is performed by the scientists to explain the process taking place in the world and answer the questions related to various  aspects of the world whether it could be biological, physical or chemical.

Discoveries in the biological world date back in B.C when Aristotle for the first time divided the living world from the non-living world and classified the living organisms on the basis of the color of the blood.

Thus, the scientific method is the correct answer.

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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.