Respuesta :
a lot is going to change like for example From the Civil War to the end of the century lumbering and flour and grist milling were the leading industries, except that cottonseed crushing supplanted flour and grist milling in second rank, according to the census of 1900. i think this because there was a lot that off things they didn't have before that they have now.
Answer:
Oil was the most important. It was used for fuel, machinery, medicine, and lighting. To this day, Oil is still important. We use it as gasoline for some cars, it is also still the fuel for machines.
Explanation:
I wrote that and got a 100, also sorry for the late answer.