Which urban model was developed to explain the patterns of American cities in the 1920s? sector model
central place model
multiple nuclei model
urban reaims model
concentric zone​

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.

Mosses, lichens and shrubs can be found where in russia? a. grasslands b. mountain regions c. coastal plains d. siberian tundra

What border separates sonora and chihuahua national border state border physical boundary natural boundary