answer: #Person2# is going to New York with #Person1#. #Person1# tells #Person2# 'Big Apple' is the nickname for the city and it came from some musicians of the 1920s.
documents: #Person1#: Are you ready for the trip to the 'Big Apple'?
  #Person2#: 'Big Apple'? What do you mean?
  #Person1#: 'Big Apple' is the nickname for New York City. Are you going to New York with us, or aren't you?
  #Person2#: Yes, I'm going. I'm especially looking forward to visiting a special show on modern American painters there. But tell me, where did the nickname come from?
  #Person1#: Some of the musicians of the 20s gave it the name. When they played a concert in New York in the 1920s, the musicians called it the 'Big Apple'.
  #Person2#: Amazing. New York is such an interesting place and it even has an interesting nickname.