We Observe Neutral Hydrogen Gas Using

question 34

Multiple Choice

We observe neutral hydrogen gas using

• A) X-ray radiation from highly ionized atoms.
• B) visible radiation at 656.3 nm from recombined hydrogen.
• C) 21-cm emission.
• D) microwave emissions.
• E) ultraviolet radiation from helium and oxygen.

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Definitions:

Two-tail Test

A statistical test in which the critical area of a distribution is two-sided and tests whether a sample is either greater than or less than a range of values.

Nominal Data

Data that represents categories with labels or names, where the order of the categories is not meaningful.

Z-test

A statistical test used to determine whether two population means are different when the variances are known and the sample size is large.

Chi-square Test

A statistical test used to determine if there is a significant difference between the observed frequencies and the expected frequencies in one or more categories.