About how many immigrants came to the united states between 1820 and 1830​

Until the middle of the 19th century, immigrants had been arriving at a slowly increasing rate: 8,385 in 1820; 23,322 in 1830; and 84,066 in 1840. Between 1830-39 over 538,381 arrived but the next ten years saw this increase to 1,427,337. In 1854 a record 428,000 people arrived in the United States.

most people now work in jobs where they do one  kind  of work; they are carpenters, bankers, cooks, mechanics, and so forth. likewise, most  businesses produce  only certainkinds  of  goods  or  services, such as cars, tacos, or gardening  services. this feature of  production  is known as specialization.