A star is moving towards the earth with a speed at 90% the speed of light. It emits light, which moves away from the star at the speed of light. Relative to us on earth, what is the speed of the light moving toward us from the star?
A) 0.90c
B) c
C) 1.1c
D) 1.20c
E) 1.9c
B
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What is the sign of these fields’ divergence at point P on each diagram? (Hint: Draw a cross-sectional view of a small div-meter centered on the point in question, and sketch the electric field vectors at the midpoint of each of the div-meter’s four sides in the drawing’s plane. Don’t worry about how we might create such a field. 
A. The divergence is positive. B. The divergence is negative. C. The divergence is zero.
In age, Galactic disk stars are typically much ________ than those of the Galactic halo
Fill in the blank(s) with correct word
The temperature of the photosphere is about
A) 3,200 K. B) 5,800 K. C) 11,000 K. D) one million K. E) ten million K.
A few decades ago, there was great controversy among astronomers over the question of quasar distances, with some arguing that quasars are much nearer than application of Hubble's law would seem to imply
Why do nearly all astronomers now agree that quasars really are quite far away? A) We now have images and spectra that show quasars to be embedded at the centers of distant galaxies and within distant galaxy clusters. B) All quasars have large redshifts. C) Now that we can explain bright quasar emission with power due to the presence of supermassive black holes, there is no reason to doubt that quasars are far away. D) No one could think of a way to explain quasar speeds if they are nearby, so we concluded they must be far away.