You Observe Three Different Star Clusters and Find That the Main-Sequence

question 11

Multiple Choice

You observe three different star clusters and find that the main-sequence turnoff stars in Cluster 1 have spectral type F, the main-sequence turnoff stars in Cluster 2 have spectral type A, and the main-sequence turnoff stars in Cluster 3 have spectral type G.Which star cluster is the youngest and which one is the oldest?

• A) Cluster 1 is the youngest and Cluster 2 is the oldest.
• B) Cluster 2 is the youngest and Cluster 1 is the oldest.
• C) Cluster 2 is the youngest and Cluster 3 is the oldest.
• D) Cluster 3 is the youngest and Cluster 1 is the oldest.
• E) Cluster 3 is the youngest and Cluster 2 is the oldest.

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Definitions:

External Cues

Environmental signals or triggers that can elicit or influence behavior, emotions, or physiological responses.

Circadian Rhythm

The internal process that regulates the sleep-wake cycle and repeats on each rotation of the Earth roughly every 24 hours.

Day-Night Cycle

The 24-hour period that includes one full rotation of the Earth, leading to the natural alternation between daylight and nighttime.