Paleoindian artifacts have been found on hills and ridges overlooking streams where hunters could see a) the water levels of the streams. b) trees that could be cut down for firewood. c) the movements of game in the stream valleys. d) chert and flint sources in the rock outcroppings.

How did the technology of the late 1800s affect the growth of cities? select one: a. cities were able to expand outward because of additions to railroads. b. electric streetcars enabled the wealthy city dwellers to move to the first suburbs. c. advances in steel and metal technology allowed for the development of the skyscraper, which allowed cities to grow upwards. d. all of these are correct.