Consider a spiral galaxy that is moving directly away from Earth with a speed V = 3.600 106 m/s at its center, as shown in the figure. The galaxy is also rotating about its center, so that points in its spiral arms are moving with a speed v = 6.300 105 m/s relative to the center. Light with a frequency of 9.730 1014 Hz is emitted in both arms of the galaxy, and this light is detected by astronomers on Earth. (a) Does the arm near the top of the figure show a red shift (toward lower frequency) or a blue shift (toward higher frequency)? Does the lower arm show a red or a blue shift? EXPLAIN (b) What frequency is detected by the astronomers observing the upper arm? (Enter your answer to 4 significant figures.) (c) What frequency is detected by the astronomers observing the lower arm? (Enter your answer to 4 significant figures.)