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In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: Homework can put you in a badmood , and that might actually be a good thing. Researchers from the University of Plymouth in England doubted whether mood might affect the way kids learn. To find out the answer, they did two experiments with children. The first experiment tested 30 kids. Someshapes were hidden inside a different, larger picture. The kids had to find the small shapes while sitting in a room with either cheerful or sad music playing in the background. To test their mood, the scientists asked the kids to point to one of five faces, from happy to sad. Children who listened to cheerful music tended to point to the smiley faces while the others pointed to the unhappy ones. The researchers found that sad kids took at least a second less to find the small shapes. They also found an average of three or four more shapes. In the second experiment, 61 children watched one of two scenes from a film. One scene was happy, and the other was sad. Just like in the first experiment, kids who saw the sad scene acted better compared to the others. The researchers guessed that feeling down makes people more likely to focus on a problem or difficult situation. Not all scientists agree with them, however. Other studies argued that maybe, that cheerful music in the first experiment distracted kids from finding shapes. While scientists work on finding out the answers, it still might be wise to choose when to do your tasks according to your mood. After eating a delicious ice cream, for example, write an essay.
Answer: whether mood affects their learning ability
Solution: Researchers did experiments on kids in order to find out _ .
Why? It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment.

New input: Article: Greg Lyons waited nine years for the opportunity to donate bone marrow . The man had to wait an additional year to finally meet the little girl whose life his donation helped save. That meeting finally too place earlier this fall in the prefix = st1 /Charlotte,Mich, home of Alissa Christie. Lyons first volunteered to donate bone marrow while giving blood for a boy in need. But nine years passed and Lyonsadmittedly forgot that he was on the donor list--until he got a call in May 2005. Lyons was informed that he was a perfect one-in-seven-million match for a 7-year-old girl. For the next seven weeks, Lyonswent through a series of tests- including several blood tests as well as a lung x-ray to determine whether he was fit to donate. On July 7, 2005, Lyons was checked in to WestPennHospital, where the bone marrow was taken. One half liter of bone marrow was taken during the two-hour operation. The bone marrow was then immediately given to the girl. In August, Lyonsreceived a telephone call from the mother of the girl, Monica Christie, who gave him permission to meet the girl "Her mother cried on the telephone," Lyonssaid. Late last month, Lyons made the 7-hour drive to Michiganto meet Alissa, who is now 8 years old and said he planned to stay in touch with the family. "One chapter ended and another chapter began," said Lyons.
Answer: impossible
Solution:
According to the passage, to find a perfect match bone marrow for Alissa is _ .