Answer:
It was significant because it was the largest city in Egypt for more than two thousand years, not to mention being the capital for about half the time. The city made major profit from overland connection between the Mediterranean Sea and the Red Sea.
I forget 5
6 is MARYland (the u.s. state )
7 is new Jersey also us state
8 is the Carolinas us states ( north and south)
The main reason the United States government intervened in the Great Railroad Strike of 1877 was because it was leaving thousands of people without transportation, which meant that the US GDP was decreasing in hurting business of all kinds.