A Controlled Experiment Is One That

question 15

Multiple Choice

A controlled experiment is one that

• A) proceeds slowly enough that a scientist can make careful records of the results.
• B) tests experimental and control groups in parallel.
• C) is repeated many times to make sure the results are accurate.
• D) keeps all variables constant.
• E) is supervised by an experienced scientist.

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Definitions:

Unconformity

A surface within the rock record that represents a gap in the geological history due to erosion or non-deposition of sediments.

Petroleum

A naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons, used primarily as fuel and in chemical production.

Oil Shale

A fine-grained sedimentary rock from which liquid hydrocarbons (shale oil) can be produced, serving as a potential source of unconventional oil.

Oil Shale

Sedimentary rock containing organic matter that can be converted into shale oil through heating; a potential but controversial energy resource.