Which tools do astronomers use to determine the effects of collisions between galaxies

Which phrase describes the time it takes for a planet to make a complete rotation

Technology has affected regional settlement patterns in what ways? choose all that apply. climatic improvement strategies have improved crop productivity. mechanized agricultural methods have improved agricultural productivity. participation in the global economy has increased urbanization. population shifts from urban to rural areas has increased as a result of petroleum production. settlement areas have increased as a result of improved water storage and delivery systems.

__ has (or have) been one of the most common pull factors of migration within the united statesa. lack of humanityb. gamblingc. seafoodd. well paying jobs