Take the points and report my question too​

Shaken by the collapse of the steel industry, which had provided them with an unshakable sense of identity for more than a century, pittsburghers hunkered down and built a new economy based on services, medicine, education, and technology. in the process, they transformed their community from one driven by quantity of production into one devoted to quality of life. —peter miller, "pittsburgh: stronger than steel," national geographic, december 1991. the community remodeling carried out in pittsburgh was accomplished partly through the conversion of old factories for new uses—a process known as a. urban renewal. c. gentrification. b. retooling. d. urban pioneering.

Which theory suggested that the earth was once a signle supercontient that gradually that broke up into the contients that we know today

The earth is composed of three different chemical layers: core, mantle and crust. the formation of these layers was from a process called