What Objects Did Harlow Shapley Use as "Signposts" to Figure

question 27

Multiple Choice

What objects did Harlow Shapley use as "signposts" to figure out the extent of the Milky Way Galaxy and the location of its center?

• A) thick clouds of cold hydrogen giving off 21-cm radiation
• B) globular clusters
• C) HII regions
• D) dust clouds
• E) big arches advertising "billions and billions sold"

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Definitions:

Language Delay

A developmental delay where a child is behind in acquiring language skills compared to their peers.

Motor Skills

The abilities required to perform movements and tasks, involving the coordination between muscles and the nervous system.

Growth

An increase in some quantity over time; in biology, it refers to the process by which organisms increase in size, number of cells, or developmental complexity.

Metabolism

The set of life-sustaining chemical reactions in organisms that enables the conversion of food into energy, the construction of necessary substances, and the elimination of waste products.