In a prominent model of self-administration developed by George Koob, rats are allowed to self-administer cocaine for either 1 hour each day (short access) or 6 hours each day (long access).
Based on the description, <span>marvin is exhibiting :Decentering
Decentering is a psychological distress that happen to someone after being replaced from the center of attention.
Before Marvin's brother is born, Marvin received the full attention from his parents. But now after his brother is born, most of the attention is given to his brother, which is the most likely reason why Marvin is upset
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B. It was established to help the president perform his duties.
