 Complete the following phrase:  During its first hundred years, Chicago was one of the fastest-growing cities in the world. When founded in 1833, fewer than 200 people had settled on what was then the American frontier. By the time of its first census, seven years later, the population had reached over 4,000. In the forty years from 1850 to 1890, the citys population grew from slightly under 30,000 to over 1 million. At the end of the 19th century, Chicago was the fifth-largest city in the world, and the largest of the cities that did not exist at the dawn of the century. Within sixty years of the 