Multiple Choice
Which of the following statements concerning spiral galaxies is TRUE and provides a possible reason for the differences between different classes of spiral galaxies Sa, Sb, and Sc?
A) The fraction of their total mass, which in the form of dust and gas is different; Sa has the lowest fraction whereas Sc has the highest.
B) The rate of star formation in their central bulges is different; the rate is highest for Sa type and lowest for Sc type.
C) The ratio of dust to gas in the interstellar medium is different in these types of galaxies; Sa has the most dust whereas Sc has the most gas.
D) The fraction of their total mass, which in the form of dust and gas is different; Sa has the highest fraction whereas Sc has the lowest.
Correct Answer:
Verified
Correct Answer:
Verified
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