Which Cluster Is 10 Billion Years Old

question 20

Multiple Choice

Which cluster is 10 billion years old?

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Definitions:

Placebo

An inert or non-therapeutic substance given to a control group in clinical trials to compare the effects against those of the actual drug.

Relapsed

The return of a disease or the recurrence of symptoms after a period of improvement or recovery.

Cognitive-Behavioral

A corrective methodology aimed at addressing ineffective emotional states, behaviors, and cognitive processes through a systematically planned, objective-centered framework.

Apathy

A lack of interest, enthusiasm, or concern, often manifesting as an indifference to aspects of life that typically invoke emotional responses.