Scientists Have Found Many Stars in the Outer Halo That

question 21

Multiple Choice

Scientists have found many stars in the outer halo that ________ the rotation of the galactic disk and have a very ________ fraction of heavy elements.

• A) move in a direction opposite to; high
• B) move in a direction opposite to; low
• C) move in the same direction as; high
• D) move in the same direction as; low
• E) don't move at all with respect to; low

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Definitions:

Critical Value

A point on the scale of the test statistic beyond which we reject the null hypothesis; it marks the threshold for significance.

Hypotheses

Proposed explanations or predictions that can be tested through research and experimentation.

T-statistic

A type of statistic used to estimate the population parameter based on a sample statistic.

Sample Means

The average values obtained from multiple small groups (samples) taken from a larger population, used in statistical analyses.