Spanish. I see and hear some Portugese too, because we are close to the border with Brazil, where Portugese is the official language. Many food and product labels here are written in Portugese, which isn't too hard to read if you speak Spanish.
The Uruguayan peso. The current exchange rate is 1 USD = 33.8 Uruguayan pesos.
20-30 pesos (a little less than 1 USD).
I had a really good hamburger from a food truck in the city center here. It was really cheap too, only 80 Uruguayan pesos, which is slightly more than 2 USD. From what I've been told (and from what I've seen of the cows), the beef is all grass-fed here. That might explain why beef just tastes better to me in Uruguay!
Two teachers at the liceo (high school) where I work are in a rock/pop cover band, and they have invited me to sing a few songs with them at their next performance! The songs they want me to sing are Adele's Rolling in the Deep, and Zombie by the Cranberries, which I thought was pretty funny, but I agreed. The performance is the Saturday after next at a local restaurant.