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.

[Q]: proper question: In what theory is the idea of a number exchanged with that of an ideal? 
 disfluent question: In what type of ideals no theory is the idea of a number exchanged with that of an ideal? 
 context: In ring theory, the notion of number is generally replaced with that of ideal. Prime ideals, which generalize prime elements in the sense that the principal ideal generated by a prime element is a prime ideal, are an important tool and object of study in commutative algebra, algebraic number theory and algebraic geometry. The prime ideals of the ring of integers are the ideals (0), (2), (3), (5), (7), (11), … The fundamental theorem of arithmetic generalizes to the Lasker–Noether theorem, which expresses every ideal in a Noetherian commutative ring as an intersection of primary ideals, which are the appropriate generalizations of prime powers.
[A]: ring theory


[Q]: proper question: Where is Biraben from? 
 disfluent question: Where is Geoffrey Parker or rather Biraben sorry? 
 context: The plague repeatedly returned to haunt Europe and the Mediterranean throughout the 14th to 17th centuries. According to Biraben, the plague was present somewhere in Europe in every year between 1346 and 1671. The Second Pandemic was particularly widespread in the following years: 1360–63; 1374; 1400; 1438–39; 1456–57; 1464–66; 1481–85; 1500–03; 1518–31; 1544–48; 1563–66; 1573–88; 1596–99; 1602–11; 1623–40; 1644–54; and 1664–67. Subsequent outbreaks, though severe, marked the retreat from most of Europe (18th century) and northern Africa (19th century). According to Geoffrey Parker, France alone lost almost a million people to the plague in the epidemic of 1628–31.
[A]: None


[Q]: proper question: At Millingen aan de Rijn where the Rhine splits, what does it change it's name to? 
 disfluent question: At Millingen aan de Rijn where the Waal no Rhine splits, what does it change it's name to? 
 context: The shape of the Rhine delta is determined by two bifurcations: first, at Millingen aan de Rijn, the Rhine splits into Waal and Pannerdens Kanaal, which changes its name to Nederrijn at Angeren, and second near Arnhem, the IJssel branches off from the Nederrijn. This creates three main flows, two of which change names rather often. The largest and southern main branch begins as Waal and continues as Boven Merwede (upper Merwede), Beneden Merwede (Lower Merwede), Noord River (North River), Nieuwe Maas (New Meuse), Het Scheur (the Rip) and Nieuwe Waterweg (New Waterway). The middle flow begins as Nederrijn, then changes into Lek, then joins the Noord, thereby forming Nieuwe Maas. The northern flow keeps the name IJssel until it flows into Lake IJsselmeer. Three more flows carry significant amounts of water: the Nieuwe Merwede (New Merwede), which branches off from the southern branch where it changes from Boven to Beneden Merwede; the Oude Maas (Old Meuse), which branches off from the southern branch where it changes from Beneden Merwede into Noord, and Dordtse Kil, which branches off from Oude Maas.
[A]:
Nederrijn at Angeren


