Roughly What Percentage of the Total Mass of a Galaxy

question 42

Multiple Choice

Roughly what percentage of the total mass of a galaxy is made up of luminous, or normal, matter?

• A) 5-10 percent
• B) 25-30 percent
• C) 40-50 percent
• D) 70-75 percent
• E) 90-95 percent

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Definitions:

Age-Sex Histogram

A graphical representation that shows the distribution of various age groups in a population which typically forms the shape of a pyramid.

World's Population

The total number of people living on Earth, which is subject to change due to birth rates, death rates, and migration patterns.

Seniors

Older adults or individuals who are typically 65 years or above, often considered as a demographic group with specific health, economic, and social needs.

Young-Old

A term often used to describe the segment of the elderly population considered to be in better health and more active than those who are older and potentially less healthy.