Complex sentence: The first Chinese businesses appeared in Newark in the second half of the 19th century and the early part of the 20th century and by the 1920s, the small area had a Chinese population over 3000.
Split into simpler sentences: The first Chinese businesses appeared in Newark in the second half of the 19th century and in the early part of the 20th century. By the 1920s, the small area had a Chinese population of over 3000.