Which best describes radiometric dating? a: measures the amount of radioactive materials in a sample. b: measures the breakdown of radioactive materials in a sample. c: measures the accumulation of radiometric materials in a sample. d: measures radiometrics.

The answer is; B

Rocks have naturally occurring and spontaneously radioactive atoms in them, such as carbon-14. These element isotopes decay into other types of atoms over millions of years. Therefore, by measuring the amount of these radiometric substances, and knowing the half-life of the isotopes, it is possible to postulate the age of a rock to within certain ranges of error.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.