How Do We Know the Total Mass of the Milky

question 66

Multiple Choice

How do we know the total mass of the Milky Way Galaxy that is contained within the Sun's orbital path?

• A) By applying Newton's version of Kepler's third law (or the equivalent orbital velocity law) to the Sun's orbit around the center of the Galaxy
• B) By counting the number of stars visible in this region of the galaxy
• C) By estimating the amount of gas and dust in between the stars
• D) By using the law of conservation of angular momentum to calculate the orbital speeds of nearby stars

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Definitions:

Cost Center

A part of an organization that does not directly add to profit but incurs costs, such as the customer service department.

Profit Center

A branch or division of a company that is treated as a separate entity for the purpose of revenue and profit calculation, allowing for better management and financial analysis.

Profit Center

A part or division of a business that is directly responsible for generating its own revenue and profit, allowing for assessment of performance.

General Expenses

Broad category of costs that are associated with the daily operations of a business but are not directly tied to production.