What is the relationship between decisions and trade offs

What was the main aim of the northwest ordinance of 1787

1. any body of surface water in which water is stored is a(n) aquifer reservoir channel floodplain 2.which of the following is a source of groundwater replenishment? seepage into springs infiltration from the surface evaporation all of the above 3. watersheds are bounded by points of high elevation called drainage basins. true false 4.non-native species can harm watershed environments by competing with native species for food. true false

Select the correct answer. what was edwin hubble's contribution to the field of astronomy? a. he discovered variable stars. b. he proved that the heliocentric model accurately described our solar system. c. he found a relationship between the period luminosity and distance of stars. d. he proved that the universe is finite. e. he discovered that the universe was expanding.