Who was John C. Calhoun and what did he believe?

John C. Calhoun loved his country. But he also loved his home state of South Carolina, and he supported its institution of slavery. He believed in states' rights that if a state didn't believe a federal law was constitutional, it didn't have to obey it.

all of the choices are correct

in february 1787, congress decided that a convention should be convened to revise the articles of confederation, the nation’s first constitution. in may, 55 delegates came to philadelphia, and the constitutional convention began. debates erupted over representation in congress, over slavery, and over the new executive branch. the debates continued through four hot and muggy months. but eventually the delegates reached compromises, and on september 17, they produced the u.s. constitution, replacing the articles with the governing document that has functioned effectively for more than 200 years.