Correct Answer: B. Maine
The US Congress passed a law that admitted Missouri to the Union as a slave state AND MAINE AS A FREE STATE.
I bet many things happened in 1790, on Brain.ly you need to be more specific. :)
One of the main reasons Rome did not expand farther north was because this area was inhabited by several hostile tribes and groups, that became too much of a headache for the Romans.
Most likely copper, iron, and nickel.
