Help me with these art questions please

In areas where even the experts disagree; everyone has a right to his own opinion. i mean if answers aren’t given just like in lots of things; then it has to be just anyone’s opinion. is this dualism multiplicity relativism or commitment

Which style of polyphony uses a borrowed chant and arranges several new melodies and texts above and unrelated to the chant?

What is the name of the song released by the artist "owl city" in 2009 as a hit single? (it was also one of the dankest memes of 2017)