Answer:
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Explanation:
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Here’s one sorry Industrial expansion and population growth radically changed the face of the nation's cities. Noise, traffic jams, slums, air pollution, and sanitation and health problems became commonplace. Mass transit, in the form of trolleys, cable cars, and subways, was built, and skyscrapers began to dominate city skylines.
The Hellenistic Erasistratus discovered the heart was the pump to push blood through the arteries.
Aristarchus developed the theory that the sun was the center of the universe.
Euclid wrote the basic geometry book, Elements, that was used for 2000 years.
Hero of Alexandria devised the first steam engine although he considered it merely a toy.
Isaac Singer<span>. </span>Isaac Merritt Singer<span> (October 27, 1811 – July 23, 1875) was an American inventor, actor, and businessman. He made important improvements in the design of the sewing machine and was the founder of the </span>Singer<span> Sewing Machine Company. have a nice day!</span>