I believe the answer is: It was located on peninsula between Europe and Asia and lied on the cross of trade routes
This location gave constantinople a strategic location to control the trades between European traders and Asian traders. They could obtain a lot of profit by either taxing the trades that pass through their territory, or monopolizing a certain type of product themselves.
The late 19th-century United States is probably best known for the vast expansion of its industrial plant and output. At the heart of these huge increases was the mass production of goods by machines. This process was first introduced and perfected by British textile manufacturers.
In the event of the president's death during the term or resignation, the vice president becomes president, followed by the Speaker of the House.
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