Which of the Following Is True of the Pleistocene Ice

question 119

Multiple Choice

Which of the following is true of the Pleistocene ice sheets in North America?

• A)at their maximum,they extended to the present-day Canada/U.S.border.
• B)they had a minimal effect on the landscape.
• C)they completely disappeared by 7,000 years ago.
• D)the edges of the ice sheets were not even rather,they were characterized by ice lobes that formed curved edges.
• E)all of North America was covered with ice at the Pleistocene maximum.

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Definitions:

External Validity

Relates to whether an experiment has in fact captured the external world that the researcher is investigating.

Attrition

The loss of participants during the course of a study, which can impact the study's outcomes and generalizability.

Nonprobability Sampling

Sampling based on a judgment by the researcher.

Random Assignment

A method in research design that allocates participants to different groups purely based on chance, ensuring that each participant has an equal opportunity to be assigned to any given group.