Answer:
Delaware, Maryland, that's pretty much it
More Americans were able to buy homes after the WWII because of the purchasing power of the American Dollar. In order for the country to experience a drastic economic change, it had to change its policies about taxes, cost of living, and personal wages of its people. So during that time period, people had a lot of money and decided to change their old ways of living in the city and moving into the suburbs to buy a lot and build their own houses there. They found that life was more peaceful and quaint as compared to the city life that's why there was a boom in suburban life after the WW.
One of the main ways in which changes to the railroad helped American industries to grow is that the expansion of the rail system led to increased migration to the west, which led to more farming and agricultural output. Another would be that it led to settlements that ultimately led to business that were able to conduct business over state lines with great ease.
