How do observations of distant galaxies us learn about galaxy evolution? a. observations at different distances show galaxies of different ages and therefore different stages of evolution. b. we can observe the birth of galaxies. c. we can observe the evolution of a single galaxy over time. d. we can observe two galaxies merging and what the result is, us learn how mergers affect evolution. e. we can see what our galaxy used to look like and therefore theorize about the physical processes that led to its current appearance?

Match your vocabulary word to its definition. 1. emigration 2. immigration 3. migration 4. overpopulation 5. sustainable development 6. under population 7. unsustainable development 8. urbanization the movement from one place to another the number of people exceeds the available natural resources in an area leaving one's homeland to settle in a new place the increase in the population of a city the movement of people to a new country the ability to meet current needs without reducing the ability to meet future needs resources being used up at a faster rate than they can be replenished birth rate insufficient to replace the existing population