For Finding the Distance to M31, Hubble Relied Upon

question 2

Multiple Choice

For finding the distance to M31, Hubble relied upon

• A) Cepheid variables in its spiral arms.
• B) planetary nebulae near its core.
• C) RR Lyrae stars in its globular clusters.
• D) Type I supernova in its core.
• E) Type II supernova in its spiral arms.

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Definitions:

Cross-Sectional Studies

Observational studies that analyze data from a population, or a representative subset, at a specific point in time.

Clinical Phase

A stage in the research and development process of new medical treatments that involves testing on human subjects to evaluate efficacy and safety.

Natural History

The course a disease takes in the absence of intervention, from its onset through its eventual resolution or progression to death.

Ultimate Outcome

The final or most significant result or consequence of a series of events or actions.