A Graduate Student in Astronomy Needs to Measure the Mass

question 31

Multiple Choice

A graduate student in astronomy needs to measure the mass of a spiral galaxy she is studying for her PhD thesis. Which of the following observations would be important for her to make?

• A) determine whether or not there is evidence for a massive black hole at the galaxy's center
• B) construct an H-R diagram for a prominent open cluster in the galaxy's disk
• C) measure the gamma-ray emission from the galaxy
• D) compare the overall color of the galaxy to other galaxies of the same type
• E) obtain the speed at which stars or gas near the outer regions of the galaxy are moving around

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Definitions:

Time Value

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Out-of-the-money

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In-the-money

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