You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
Use a disfluent question or a proper question and find the answer to the question based on the given context or return None if an answer can't be found. A disfluent question is a question that has some interruptions in it while framing. A proper question is the correct form of the question without any disfluency.

proper question: In what year did the U of C become one of 7 founding members of the Association of Chicago Universities?
disfluent question: In what year did Robert Harper or did the U of C become one of 7 founding members of the Association of Chicago Universities?
context: Founded by the American Baptist Education Society with a donation from oil magnate and wealthiest man in history John D. Rockefeller, the University of Chicago was incorporated in 1890; William Rainey Harper became the university's first president in 1891, and the first classes were held in 1892. Both Harper and future president Robert Maynard Hutchins advocated for Chicago's curriculum to be based upon theoretical and perennial issues rather than on applied sciences and commercial utility. With Harper's vision in mind, the University of Chicago also became one of the 14 founding members of the Association of American Universities, an international organization of leading research universities, in 1900.
Solution: None
Why? The answer to the above question is not found from the context hence it is not answerable so the output is 'None' so it is a positive example.

New input: proper question: What did Mote think the Yuan class system didn't represent?
disfluent question: What did Mongols think the Yuan class system didn't represent no no what did Mote think?
context: The historian Frederick W. Mote wrote that the usage of the term social classes for this system was misleading and that the position of people within the four-class system was not an indication of their actual social power and wealth, but just entailed degrees of privilege to which they were entitled institutionally and legally, so a person's standing within the classes was not a guarantee of their standing, since there were rich and well socially standing Chinese while there were less rich Mongol and Semu than there were Mongol and Semu who lived in poverty and were ill treated.
Solution:
None