Protostars with Emission Lines as Well as Absorption Lines in Their

question 85

Multiple Choice

Protostars with emission lines as well as absorption lines in their spectra and whose luminosity can change irregularly as they eject material into space are

• A) asymptotic giant branch stars.
• B) T Tauri stars.
• C) red-giant stars.
• D) main-sequence stars.

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Definitions:

Learning Association

A process by which two pieces of information, or a behavior and a response, become linked in the mind or behavior of an individual.

Operant Conditioning

A method of learning that employs rewards and punishments for behavior.

Involuntary Responses

Reflex actions or responses that occur without conscious control, typically as automatic reactions to stimuli.

Voluntary Responses

Actions that are performed intentionally or with conscious control, often in contrast to reflexive or automatic responses.