If the Rotational Speed of the Gas in the Disk $\odot$

question 90

Multiple Choice

If the rotational speed of the gas in the disk of a spiral galaxy is 200 km/s at a distance of 25,000 pc from its center, then what is the mass enclosed within this radius?

• A) 7.5 billion M _\(\odot\)
• B) 18 billion M _\(\odot\)
• C) 70 billion M _\(\odot\)
• D) 230 billion M _\(\odot\)
• E) 400 billion M _\(\odot\)

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Definitions:

Tolerances of Size

Specifies the permissible limits of variation in an object's size, critical for ensuring parts fit together properly in manufacturing.

Cylindrical Tolerance Zone

A specified range of acceptable measurements or dimensions for the diameter or roundness of cylindrical parts, ensuring proper fit and function.

Specified Tolerance

The permissible limit or range of variation defined for a dimension, material condition, or geometric characteristic.

Angularity

A geometric dimensioning and tolerancing (GD&T) term that describes the angle tolerance of a feature relative to a datum.