How did congress attempt to maintain a balance of power between northern and southern states in the mid-1800s?
a. by keeping the number of free and slave states equal
b. by creating more free states than slave states
c. by created more slave states than free states
d. by forming new political parties to address slavery

B.by creating more free states than slave states

The main way that congress attempted to maintain a balance of power between northern and southern states in the mid-1800s was " b. by creating more free states than slave states" which led to the civil war. 

In my honest opinion , i’d say franklin d roosevelt was a president that impacted our nation , i say this because fdr is voted among top three best us presidents and he was the longest serving president by 3 terms , usually presidents only supposed to have two terms increments of 4 years , equivalent to 8 years total before election time. and he established the fdic , through the 1933 banking act and he established the us , social security system , during his presidency, and established a national minimum wage , through the fair labor standards act , fdr led the allied coalition to victory in wwii and he played a major role in the creation of the united nations.