Why did the united states become a leading industrial power in the nineteenth century?

The largest city in brazil, sao paulo, has a population of about 11 million. based on the rank-size rule, what is the population of the second-largest city, rio de janeiro, most likely to be? a. 8 – 10 million b. 5 – 6 million c. about 3 million d. about 1 million

Ineed to have answers for numbers 2-4 reply to this question

What is the name for the main idea behind the settling of western lands by americans in the early-1800s?