Answer:
During the late 19th century many environmental problems caused changes and created public awareness. One problem was that the country could soon run out of vital natural resources like wood. This led many people to join the “conservation movement” in the early 20th century in order for future generations to have enough supplies that were made from raw materials. Another problem was the fate of the “wilderness”, so many organizations began to fight for undeveloped lands should be preserved. Lastly, one big problem was pollution. This issue was a big threat to the fast-growing cities, which led to efforts in order to improve the urban environment. There were also some changes and the popular sports. During the late 19th century the Olympic started to become an international spectacle. Apart from that there were also many games like baseball that started to grow in popularity. Due to many segregational beliefs during this time there were many only African American teams that were created.
One last thing that changed during the nineteenth and twentieth century was the art of the United States. Abstract expressionist movements started after World War II. Later came minimalism and pop art.
Step-by-step explanation: