In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.

[Q]: Context: Daxing was renamed Chang'an in year 618 when the Duke of Tang, Li Yuan, proclaimed himself the Emperor Gaozu of Tang. Link Information: born Li Yuan, courtesy name Shude, was the founder of the Tang dynasty of China, and the first emperor of this dynasty from 618 to 626. Answer: 8
[A]: How many years did Duke of Tang serve as emperor after renaming Daxing, Chang'an?


[Q]: Context: Duffy later appointed New York regional administrator of the Securities and Exchange Commission office (1969–1972). His tenure as Regional Administrator of the United States Securities and Exchange Commission was in a time of turmoil in Wall Street. Link Information: none Answer: none
[A]: What turmoil was Wall Street facing during Duffy's tenure as Regional Administrator of the United States Securities and Exchange Commission?


[Q]: Context: Homer putting the flowers in the policemen's rifles is a reference to the iconic October 22, 1967 Life magazine picture, "Flower Power" by Bernie Boston. Link Information: Bernie Boston (May 18, 1933 Answer: 34
[A]:
What age was the photographer who took the picture that Homer referenced, when the photograph was printed?