A Cepheid variable star in a spiral galaxy appears roughly 108times fainter (on average) than an identical Cepheid observed in the Milky Way Galaxy, whose distance is 1,000 parsecs. Using the inverse square law, calculate the distance to the nearby galaxy

Which of the following conditions lead you to see an absorption line spectrum from a cloud of gas in interstellar space? the cloud is extremely hot. the cloud is visible primarily because it reflects light from nearby stars. the cloud is cool and lies between you and a hot star. the cloud is cool and very dense, so that you cannot see any objects that lie behind it.