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.

Example Input: proper question: Why has the Rhine been shortened? 
 disfluent question: Where does um wait why has the Rhine been shortened? 
 context: The length of the Rhine is conventionally measured in Rhine-kilometers (Rheinkilometer), a scale introduced in 1939 which runs from the Old Rhine Bridge at Constance (0 km) to Hoek van Holland (1036.20 km). The river length is significantly shortened from the river's natural course due to number of canalisation projects completed in the 19th and 20th century.[note 7] The total length of the Rhine, to the inclusion of Lake Constance and the Alpine Rhine is more difficult to measure objectively; it was cited as 1,232 kilometres (766 miles) by the Dutch Rijkswaterstaat in 2010.[note 1]
Example Output: from the river's natural course due to number of canalisation projects completed in the 19th and 20th century

Example Input: proper question: What was eventual Merits role? 
 disfluent question: Where was no What was eventual Merits role? 
 context: Merit Network, Inc., an independent non-profit 501(c)(3) corporation governed by Michigan's public universities, was formed in 1966 as the Michigan Educational Research Information Triad to explore computer networking between three of Michigan's public universities as a means to help the state's educational and economic development. With initial support from the State of Michigan and the National Science Foundation (NSF), the packet-switched network was first demonstrated in December 1971 when an interactive host to host connection was made between the IBM mainframe computer systems at the University of Michigan in Ann Arbor and Wayne State University in Detroit. In October 1972 connections to the CDC mainframe at Michigan State University in East Lansing completed the triad. Over the next several years in addition to host to host interactive connections the network was enhanced to support terminal to host connections, host to host batch connections (remote job submission, remote printing, batch file transfer), interactive file transfer, gateways to the Tymnet and Telenet public data networks, X.25 host attachments, gateways to X.25 data networks, Ethernet attached hosts, and eventually TCP/IP and additional public universities in Michigan join the network. All of this set the stage for Merit's role in the NSFNET project starting in the mid-1980s.
Example Output: None

Example Input: proper question: In what year were the oldest additions in Hong Kong opened? 
 disfluent question: When was no in what year were the oldest additions in Hong Kong opened? 
 context: The University of Chicago also maintains facilities apart from its main campus. The university's Booth School of Business maintains campuses in Singapore, London, and the downtown Streeterville neighborhood of Chicago. The Center in Paris, a campus located on the left bank of the Seine in Paris, hosts various undergraduate and graduate study programs. In fall 2010, the University of Chicago also opened a center in Beijing, near Renmin University's campus in Haidian District. The most recent additions are a center in New Delhi, India, which opened in 2014, and a center in Hong Kong which opened in 2015.
Example Output:
None