What Is a Rotation Curve

question 62

Multiple Choice

What is a rotation curve?

• A) A graph showing how orbital velocity depends on distance from the center for a spiral galaxy
• B) A precise description of the shape of a star's orbit around the center of the Milky Way Galaxy
• C) A curve used to decide whether a star's orbit places it in the disk or the halo of a spiral galaxy
• D) A graph that shows a galaxy's mass on the vertical axis and size on the horizontal axis

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Definitions:

Environmental Protection

Efforts and policies aimed at safeguarding the natural environment from degradation due to human activities, ensuring the health and sustainability of ecosystems.

Scientific Research

The systematic investigation and study of materials, sources, etc., in order to establish facts and reach new conclusions.

Social Security Tax

A tax imposed on both employers and employees used to fund the Social Security program, which provides retirement, disability, and survivorship benefits.

Wage-Base Limitation

A wage-base limitation refers to the maximum amount of earnings that is taxed for certain social services, such as Social Security, beyond which earnings are no longer subject to the tax.