31. Nearly every galaxy known has a spectrum that: A.) Shows only emission lines B.) Is blueshifted C.) Is redshifted D.) Is yellowshifted 32. Which of these is NOT TRUE of Gravitational lensing? A.) it is the principle by which refracting telescopes work. B.) Einstein's General theory of relativity predicts it C.)t is a distortion of light due to mass D.) it has been used to measure large quantities of dark matter 33. The "Cosmic Horizon", the greatest distance we can hope to see, is: A.) infinitely far away because the Universe is infinite B.) at the edge of the Solar System C.) about 13.7 billion light years away. D.) at the edge of the Milky Way Galaxy 34. The Cosmic Microwave Background (CMB) is not perfectly smooth, but has small variations on the sky. Their significance is: A.) each was produced by a supernova explosion. B.) they reveal density enhancements that resulted in the formation of galaxies. C.) they are Cepheid variable stars D.) they represent planets in formation 35. Terrestrial planets are often considered to be the best locations for life. In our solar system, the terrestrial planets are: A.) Earth & Mars B.) Jupiter, Saturn, Neptune & Uanus C.) Mercury, Venus D.) Mercury & Venus, Mars & Earth 36. What do earthquake faults and seafloor spreading ridges have in common? A.) both are known to exist on other planets B.) both are found near California C.) they are both examples of tectonic plate boundaries D.) they are both found deep in Earth's interior 37. The "Inflation Theory" of Cosmology proposes: A.) that the universe will eventua be ripped B.) that the price of everything is becoming astronomical C.) that the universe has always been expanding at the same rate D.) that the universe underwent a period of extremely rapid expansion just after the Big Bang 38. The amount of matter in the universe that is "Dark" is: A.) currently unknown B.) small compared to the about of visible matter C.) roughly 90% D.) about 1%