How did California statehood, "bleeding Kansas", and Dred Scott decision lead to the disintegration of the two national parties, Whig and Democrat, and the division of the nation, North and South?

Terrence would like to reward himself after each goal he sets, but he's not sure what type of reward to choose. he's easily distracted and finds it hard to concentrate at times. which would be the best type of reward for terrence? a. a brief social network break b. a long nap c. a snack while he keeps studying d. watching a couple of tv shows