Answer:
The concept of the "suburbs" was built up by Levitt and Sons, and this concept had become extremely successful, as over 85% of new homes within the United States are in suburban areas- and is has become a staple of American culture.
..Well, you might want to cut out the "staple of American culture" part. That's just me talking out my butt.
Cyrus McCormick in 1831. This machine was used<span> by farmers to harvest crops mechanically. For hundreds of years, farmers and field workers had to harvest crops by hand using a sickle or other methods, which was an arduous task at best</span>
Surface erosion ,fluvial erosion ,and stream bank erosion
It says the US is walking towards immigrant restrictions
