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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: Can eating a chocolate bar every day really prevent age-related memory loss? No. But a new research shows that large amounts of flavones, substances found in cocoa, tea and some kinds of vegetables, may improve age-related memory failure. Dr. Scott Small is a professor of neurology at Columbia University in new York City He is the lead writer of a research paper describing the effects of cocoa flavones on brain activity His study involved 37 volunteers aged between 50 and 69. Researchers gave them a high-level flavones drink made from cocoa beans or a low-level flavones drink. For a period of three months, some subjects got 900 milligrams of flavones a day. The others got 10 milligrams of flavones each day. Brain imaging and memory tests were given to each study subject before and after the study Dr. Small says that the subjects who had the high-level flavones drink showed much improvement on memorytests. The researchers warn that more work is needed to be done because this study was performed only on a small group. Dr. Joann Manson is the lead researcher of a four .year study involving 18,000 adults. This study will use flavones capsules The study subjects will be divided into two groups and will take two pills per day. The capsules used will all Look the same. But one group's capsules will contain flavones, while the other group will take capsules made of an inactive substance, or placebo Dr. Manson says it's not necessary for people to start eating more chocolate, because 3 person would have to eat a huge amount of chocolate to get the same level of flavones given to the Lest subjects. He adds many manufacturers have planned to remove the flavones from their chocolate products. Similarity, Dr. says a cocoa-based flavones extract may be developed in the future But he says that more studies are needed to see how much flavones is good for our health
Answer: They were asked to take two pills of flavones capsules per day
Solution:
What was done to the subjects alter Dr. Small's study?