According to Geological Evidence and Computer Models Based Upon That

question 6

Multiple Choice

According to geological evidence and computer models based upon that evidence,which statement about the concentration of oxygen in our atmosphere is correct?

• A)No oxygen was present prior to the Cambrian;oxygen levels have uniformly risen since and today's atmosphere is more oxygen rich than at any time in Earth's history.
• B)Oxygen levels were greatest during the Cambrian but have been steadily declining ever since;today's atmosphere is less oxygen rich than at any time in Earth's history since the Precambrian.
• C)Oxygen levels have generally risen during the Phanerozoic but peaked during the Mesozoic ("age of dinosaurs")and declined sharply in the Early Cenozoic.
• D)Oxygen levels have generally risen during the Phanerozoic but peaked during the Late Paleozoic ("age of coal swamp forests")and declined sharply in the Early Mesozoic.

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Definitions:

\(g ( x )\)

A function notation similar to \(f ( x )\), where \(g\) represents another function with the variable \(x\).

Thermostat

A device used to maintain the temperature of a system at a desired set point by regulating the flow of heat energy.

Degrees Fahrenheit

A temperature scale where water's freezing point is at 32 degrees and its boiling point is at 212 degrees, given standard atmospheric conditions.

Temperature

A measure of the hotness or coldness of an object or substance with reference to some standard value.