Baghdad was once a House of Wisdom — home of science, literature and arts. When the Mongols attacked, in just a period of two weeks, mosques, libraries, hospitals and palaces were destroyed. Books were thrown on the Tigris river while a lot of life has been lost. While they’re under the Mongolian Empire, the city recovered and infrastructures were reconstructed. After which, they were under the Ottoman rule until they’re in British control in 1921.
Your answer would be "There would need to be an equal number of free and slave states."
The Constitution prescribes that the Senate be composed of two senators from each State. There would need to be 25 slave states and 25 free states for there to be an equal number of senators from free states and slave states.