Look at the events of the 1850s from the point of view of a northerner. Explain who you are and then from your perspective why those events led to the Civil War in 1861. Was the war inevitable?
Just got time to answer the first. It's a simple answer. They retreated from their colonies because the second world war had left them bankrupt so they could no longer afford the expense of maintaining control
Learning how to learn is one of chief lessons in life. Asking others to do your tasks for you denies that opportunity. Which road you choose will have a big impact on how the rest of your life goes.