What Produces the 21-Cm Line That We Use to Map

question 31

Multiple Choice

What produces the 21-cm line that we use to map out the Milky Way Galaxy?

• A)atomic hydrogen
• B)ionized hydrogen
• C)molecular hydrogen
• D)carbon monoxide
• E)helium

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Definitions:

Base Value

A reference point or initial value used in financial calculations, indexes, or for measuring changes in economic indicators.

Missing Value

In data analysis, a data point that is absent or not recorded, which can affect the outcome of statistical models.

Decimal Places

The quantity of numerals located to the right side of the decimal point in a numeric value.

Missing Value

A data term referring to a value that is lost, unrecorded, nonexistent, or omitted in a dataset.