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.

Input: Consider Input: proper question: What are intermediate forwarding nodes? 
 disfluent question: What are packets no intermediate forwarding nodes? 
 context: Packet mode communication may be implemented with or without intermediate forwarding nodes (packet switches or routers). Packets are normally forwarded by intermediate network nodes asynchronously using first-in, first-out buffering, but may be forwarded according to some scheduling discipline for fair queuing, traffic shaping, or for differentiated or guaranteed quality of service, such as weighted fair queuing or leaky bucket. In case of a shared physical medium (such as radio or 10BASE5), the packets may be delivered according to a multiple access scheme.

Output: None


Input: Consider Input: proper question: How many companies were listed on the WSE on April 2009? 
 disfluent question: How many companies were listed on the PZPR no WSE on April 2009? 
 context: Warsaw's first stock exchange was established in 1817 and continued trading until World War II. It was re-established in April 1991, following the end of the post-war communist control of the country and the reintroduction of a free-market economy. Today, the Warsaw Stock Exchange (WSE) is, according to many indicators, the largest market in the region, with 374 companies listed and total capitalization of 162 584 mln EUR as of 31 August 2009. From 1991 until 2000, the stock exchange was, ironically, located in the building previously used as the headquarters of the Polish United Workers' Party (PZPR).

Output: None


Input: Consider Input: proper question: How long didn't the fighting last in Seven Years War 
 disfluent question: How long was the fighting on the mainland no change that to how long didn't the Seven Year war last? 
 context: In Europe, the North American theater of the Seven Years' War usually is not given a separate name. The entire international conflict is known as the Seven Years' War. Seven Years refers to events in Europe, from the official declaration of war in 1756 to the signing of the peace treaty in 1763. These dates do not correspond with the fighting on mainland North America, where the fighting between the two colonial powers was largely concluded in six years, from the Battle of Jumonville Glen in 1754 to the capture of Montreal in 1760.


Output: None