
Here's a complex question that requires someone to reason about the input, can you answer it?
Finland won the first Eurovision Dance Contest in 2007, in 2008, Finland were represented by singer and actress Maria Lund, and dancer Mikko Ahti, danced a Tango,a Tango is a partner dance, that originated in the 1880s, along which location, the natural border between Argentina and Uruguay?


River Plata
