1: Subordinate
2: Subordinate
3: Main
4: Subordinate
5: Main
6: Subordinate
7: Main (I believe)
8: Main
9: Subordinate
10: Subordinate
The subordinate clauses cannot stand on their own: they leave a hanging question. The majority of them also start with a coordinating conjunction, and that's a common thing in subordinate clauses. The main clauses can stand by themselves, as it can be seen as a whole sentence.
Answer: The first sentence
Lincoln's House Divided Speech. ... A house divided against itself cannot stand. I believe this government cannot endure, permanently, half slave and half free. I do not expect the Union to be dissolved — I do not expect the house to fall — but I do expect it will cease to be divided.