To measure the activity of the human brain during certain thought processes, a short-lived radioactive sugar is injected in the carotid artery and is utilized by those cells that are most active. This shows up on a PET scan and demonstrates the detection of ___.

The correct answer is: isotopes.

Explanation:

PET scan (positron emission energy) is an imaging technique that is used to help in the diagnosis of a disease by observing metabolic processes in the body.

PET scans, although very expensive, are of great utility in the fields of Oncology, Neurology and Cardiology.

Isotopes are atoms that share the same number of protons and electrons but differ in the number of neutrons. This gives the isotopes different properties than regular atoms. In PET, isotopes are radiotracers used to discern the biologic pathway of any compound.

option number one would be youre best option

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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