Evidence of Massive Amounts of Hydrogen Gas Surrounding Some Stars

question 34

Multiple Choice

Evidence of massive amounts of hydrogen gas surrounding some stars comes from:

• A) observation of the reddening of the spectra of these stars because of absorption of blue light by hydrogen.
• B) observation of emission of characteristic red Balmer light from nebulosity around them.
• C) theoretical calculations that correctly describe stellar formation by the gravitational contraction of hydrogen gas.
• D) observation of the blue glow from scattered light in their reflection nebulae.

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Definitions:

Compacting Database

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The action of writing changes or updates to a database file on disk, ensuring that all modifications are permanently stored.

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A feature in database software that allows users to define the structure of a table including its fields, data types, and primary keys.

Table Design View

A feature in database applications that allows users to define or modify the structure of a table, including fields, data types, and relationships.