A Sample of an Ancient Sedimentary Rock Contains Slightly Less

question 26

Multiple Choice

A sample of an ancient sedimentary rock contains slightly less of the isotope carbon-13 than normal. One possible explanation for this is that

• A) it was a meteorite that fell from the sky
• B) some kind of radioactive decay occurred in it in the past
• C) it used to be at the bottom of an ancient ocean
• D) some kind of biological activity occurred in it in the past

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Definitions:

Speech Deficits

Impairments or disorders that affect a person's ability to communicate verbally in a clear and understandable manner.

Retrieval Cues

Stimuli or prompts that enable or enhance the recall of information from memory.

Recall

The mental process of retrieving information or events from the past without being explicitly prompted.

Storage

The process of retaining encoded information over time.