Eco-201 Help

So Week 2 and I have not finished my quiz yet. I keep reading the chapter over and over but I am struggling to understand something and can't figure out what I am not understanding. One minute I think I finally understand and get it right and then the next I am getting math incorrect this time or mixing up words that are used.

Are there any YouTube videos out there for Eco-201 that helped you? I am desperate.