So that was first period. Second period we continue doing chemical balancing and then in third period we continue talking about the point of view from the north, the south and the west, focusing on certain arguments between the sections that cause led up to the Civil War. Then in the fourth period I continued with a project for the bookfeed that I'm going to have to present tomorrow. So that'll be indistinguishing luck on that and yeah, so if you have any comments you should let me know