If the Milky Way Formed Stars at Approximately a Constant $\odot$

question 56

Multiple Choice

If the Milky Way formed stars at approximately a constant rate over the last 14 billion years, what fraction of the M-type stars that ever formed in it can still be found as main-sequence stars today? Note that M-type stars have a mass of approximately 0.5 M _$\odot$ .

• A) 10 percent
• B) 33 percent
• C) 50 percent
• D) 75 percent
• E) 100 percent

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