The ¹⁴C Activity of Some Ancient Peruvian Corn Was Found

question 25

Multiple Choice

The ¹⁴C activity of some ancient Peruvian corn was found to be 10 disintegrations per minute per gram of carbon. If present-day plant life shows 15 dpm/g, how old is the Peruvian corn? The half-life of ¹⁴C is 5730 yr.

• A)1,455 yr
• B)1,910 yr
• C)3,350 yr
• D)3,820 yr
• E)9,080 yr

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Definitions:

Classical Conditioning

A learning technique involving the frequent pairing of two stimuli, so that a response originally stimulated by the second of the stimuli is in the end stimulated by only the first stimulus.

Law Of Effect

A principle in psychology stating that behaviors followed by positive outcomes are likely to be repeated, whereas behaviors followed by negative outcomes are less likely to be repeated.

Variable-Interval Schedule

A reinforcement schedule in operant conditioning where a response is rewarded after an unpredictable amount of time has passed.

Counterconditioned

The process of changing a previously undesirable response to a stimulus into a desirable one through conditioning.