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In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.

Article: There are a lot of public libraries in Britain. These libraries have more than one hundred and fifteen million books, not including those libraries of public schools. Public libraries not only lend books, music records but also help children, patients in hospitals and others to get special play readings, film shows and so on. The first public libraries were founded in about the year 1850. Today's public libraries usually have a reading-room, a lending room and a reference room. The greatest and most famous library in Britain is that of the British Library in London. It was founded in 1973 and has over 10, 000, 000 books. It has nearly every magazine, newspaper and book published in Britain and other parts across the world. 
 Answer: 10,000,000 or less.
Solution: How many books are there in the British Library?
Why? In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

New input: Article: The Ancient Town of Fenghuang, one of China's most well-known ancient towns, was under water as heavy rain hit the center of the country, with tens of thousands of people leaving from the area. Heavy rain and floods  lasted for the past few days. Waters in the nearby Tuojiang River rose by almost one meter above warning level , causing heavy rainstorms. More than 120,000 local people and tourists have been helped to leave there because of the terrible _ . And more than 4,000 shops in the town have been shut. Several bridges on the Tuojiang River have been damaged or destroyed. Water has flowed  into many bars, restaurants and hotels in its ancient town, and electricity in the ancient town has been cut off. About 128,000 people have been affected by the floods. Though the heavy rains have stopped, but the popular tourist spot remains closed for local people's safety. A shoe shop owner named Kuang said the flood was the worst the town had experienced. "The floods came so quickly that I didn't have time to move the shoes," he said sadly. "The flood has led to Fenghuang old town becoming a water town." said a post on a discussion page on the topic set up on Sina Weibo, a Chinese version of Twitter. "We could only live in an old factory now where many homeless people have to stay together. The crowded space is full of sadness." Tang said. At least 14 people were killed in flooding in Hunan Province and the neighboring province of Jiangxi and region of Guangxi last month, Xinhua reported. 
 Answer: Because of the serious flood.
Solution:
Why did many people try to leave the Ancient Town of Fenghuang?