Why Do the H-R Diagrams of Young Clusters Show the Least

question 18

Multiple Choice

Why do the H-R diagrams of young clusters show the least massive stars located above the zero-age main sequence?

• A)They are always the first stars to form in a cluster
• B)They take longer to reach the main sequence
• C)They evolve away from the main sequence before more massive stars do
• D)They are actually binaries,and thus seem overluminous

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Definitions:

Dental Caries

Tooth decay caused by bacterial infection that leads to demineralization and destruction of the hard tissues of the teeth.

Pulp Cavity

The central part of a tooth containing connective tissue, blood vessels, and nerves.

Dentin

Bony material forming the mass of the tooth.

Enamel

Hard substance covering the exposed portion of the tooth.