A Rock Sample Contains 1/8 Micrograms of the Parent Radioactive

question 33

Multiple Choice

A rock sample contains 1/8 micrograms of the parent radioactive isotope Aluminum-26 and 7/8 micrograms of its daughter isotope Magnesium-40. If the half-life of this decay is approximately 700,000 years, how old is this rock?

• A) 2.1 million years
• B) 2.8 million years
• C) 1.4 million years
• D) 700,000 years

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Definitions:

Instrumental Conditioning

A learning process in which behavior is modified by the consequences of the behavior, reinforcing desired behaviors and discouraging undesired ones.

Classical Conditioning

A learning process identified by Ivan Pavlov that occurs through associations between an environmental stimulus and a naturally occurring stimulus.

Sleep Cycle

The progression through various stages of sleep, including REM (rapid eye movement) and non-REM phases, which repeats several times throughout a typical night's sleep.

REM

Rapid Eye Movement, a sleep phase characterized by eye movement, increased brain activity, and vivid dreaming.