How did the location of philadelphia and new york them to become major colonial trading center

so the story tells of someone named kaushik choudhuri, but he does not narrate the story, a girl named hema does. hema tells the story in a second person point of view because you (the reader) are supposed to be the boy named kaushik.

here's an excerpt i found: "i was ushered into the fitting room, your mother watching approvingly as i took off my coat and sweater and tried on the bra."

source:

it affected it because the kingdoms (with trade) slowly got richer and richer.