Two Stars Are at Rest Relative to Each Other $68.7 \text { light-years }$

question 73

Multiple Choice

Two stars are at rest relative to each other. In their common rest frame, these stars are 90.0 light-years apart. If they are measured to be $68.7 \text { light-years }$ apart by the navigator of a spaceship traveling between them, how fast is the spaceship moving relative to these stars?

• A)0.646c
• B)0.604c
• C)0.558c
• D)0.505c

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Definitions:

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Relating to the body as opposed to the mind or emotions, or pertaining to physical material and phenomena in nature.

Critical Period

A specific time during development when the exposure to certain stimuli or experiences is necessary for normal development in later stages.

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Pertains to anything related to Germany, its people, culture, or language.

Plasticity

The capacity of the brain to change and adapt in response to experience, learning, or injury.