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:

Object Permanence

The understanding that objects continue to exist even when they cannot be observed directly.

Sensorimotor

Relating to or involving both sensory and motor functions or pathways, often used in reference to a stage in early child development.

Preoperational

A stage in Piaget's theory of cognitive development where children from ages 2 to 7 have increasing mental representation but do not yet understand concrete logic.

Concrete Operational

This term refers to Piaget's stage of cognitive development where children aged 7 to 11 years can think logically about concrete events and understand the concept of conservation.