What Observational Fact Convinces Astronomers That the Source of Energy

question 86

Multiple Choice

What observational fact convinces astronomers that the source of energy in a typical quasar is physically very small?

• A) rapid variation in the energy output of the source
• B) extreme distance of all quasars
• C) starlike appearance of quasars in Earth's sky
• D) narrowness of the emission lines in the spectra of quasars

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Definitions:

Cliquish Exclusion

The practice of excluding others from a social group based on group consensus or criteria, often seen in social settings like schools.

Neglected

Failing to care for properly or giving insufficient attention to, often leading to adverse outcomes.

Timid

Showing a lack of courage or confidence; easily frightened or hesitant.

Withdawn-rejected

Pertaining to individuals, especially children, who are socially withdrawn and subsequently rejected by their peers.