What Mechanism Appears to Produce the Double-Radio Sources Seen in Intergalactic

question 51

Multiple Choice

What mechanism appears to produce the double-radio sources seen in intergalactic space?

• A) two oppositely directed jets of matter, ejected from a small source
• B) two radio galaxies orbiting each other much like two binary stars
• C) a radio-bright galaxy with a dark absorbing disk edge-on to Earth, splitting the source into two as seen from Earth
• D) two black holes orbiting around a small but massive galactic nucleus

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Definitions:

Anterograde Amnesia

Lack of memory for events that occur after a brain injury. Contrast with retrograde amnesia.

Testing Effect

The experimental finding that taking tests on material actually improves the learning of it even when compared with simply repeatedly studying that material.

Roediger

Refers to Henry L. Roediger III, an influential cognitive psychologist known for his research on memory, particularly the testing effect and false memories.

Cue Overload

A principle of memory that states a retrieval cue will be most effective when it is highly distinctive and not related to any other target memories.