____________ galaxies contain a supermassive black hole at their centers while active nuclei are present in ____________of galaxies
a. Most; a few percent
b. Most; the majority
c. A small minority; a few percent
d. A small minority; the majority
Question 2
Star clusters are important to our study of stars because
a. all stars formed in star clusters.
b. the Sun was once a member of a globular cluster.
c. they give us a method to test the our theories and models of stellar evolution.
d. they are the only objects that contain Cepheid variables.
e. All of the other choices are correct.
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