Measurements Suggest That Light First Arrived at Earth from the Cassiopeia

question 18

Multiple Choice

Measurements suggest that light first arrived at Earth from the Cassiopeia A supernova about 300 years ago and that this supernova is about 10,000 ly distant from Earth.When did the explosion actually occur?

• A) It is not possible to determine when the explosion occurred from the information given.
• B) 9700 years ago, or about 7700 b.c.
• C) 10,300 years ago, or about 8300 b.c.
• D) 300 years ago, or about a.d. 1700.

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Definitions:

Preventative Facework

Efforts to maintain and enhance one’s positive self-perceptions.

Aggressive Facework

Communication strategies used to assert one's identity, often at the expense of others, through forceful or dominant behaviors.

Self-disclosure

The act of revealing personal, private, or sensitive information about oneself to others, an integral part of developing intimacy in relationships.

Self-knowledge

The understanding and awareness one has of their own character, feelings, motives, and desires.