According to Geological Evidence and Computer Models Based on That

question 9

Multiple Choice

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

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

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Definitions:

Cohesive Group

A collective of individuals who are united in their goals, values, or interests, displaying strong bonds and a high level of mutual support.

Group Attractiveness

The degree to which a group is considered appealing or desirable to its current or potential members, influenced by factors like cohesion, identity, and perceived benefits.

Group Cohesiveness

The extent to which members of a group support and validate one another while working towards a common goal.

Informal Leadership

The ability to influence and guide others without having a formal authority or position, often resulting from personal traits, expertise, or relationships.