Imagine You Discovered a Barred Spiral Galaxy That Was a "Milky

question 84

Multiple Choice

Imagine you discovered a barred spiral galaxy that was a "Milky Way twin" because the size of the bulge and disk, the arrangement of spiral arms, and other characteristics were just like those in our galaxy. Then you measured its rotation curve and plotted the figure shown below. What would you conclude about this galaxy?

• A) This galaxy has much more dark matter than does the Milky Way.
• B) This galaxy has about the same amount of dark matter as does the Milky Way.
• C) This galaxy inexplicably has much less dark matter than does the Milky Way.
• D) This galaxy probably has no stellar halo.
• E) This galaxy probably has no central black hole.

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Definitions:

Confidence Interval

A range of values computed from sample data that is likely to include the true parameter of the population with a specified level of confidence, often expressed as a percentage.

Linear Regression

A statistical method used to model the relationship between a dependent variable and one or more independent variables, adding complexity beyond simple linear regression.

Observations

Data collected or measured from a study or experiment on variables of interest.

Table Value

A specific value located in a statistical table that is used to determine the significance or critical values in hypothesis testing.