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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: Astronomers have captured the first direct image of a planet being born. Adam Kraus, of the University of Hawaii's Institute for Astronomy, said the planet is being formed out of dust and gas circling a 2-million-yea-old star about 450 light years from Earth. The planet itself, based on scientific models of how planets form, is believed to have started taking shape about 50,000 to 100,000 years ago. Called LkCa 15b, it's the youngest planet ever observed. The previous record holder was about five times older. Kraus and his colleague, Michael Ireland from Macquarie University and the Australian Astronomical Observatory, used Keck telescopes on Mauna Kea(a volcano on the island of Hawaii, US) to find the planet. Kraus presented the discovery Wednesday at NASA's Goddard Space Flight Center in Maryland. Observing planets while they're forming can help scientists answer questions like weather planets form early in the life of a star or later, and whether they form relatively close to stars or father away. Planets can change orbits after forming, so it's difficult to answer such questions by studying older planets. "These very basic questions of when and where are best answered when you can actually see the planet forming, as the process is happening right now," Kraus said. Scientists hadn't been able to see such young planets before because the stars they're circling around outshine them. Kraus and Ireland used two techniques to overcome this problem.[:++] One method, which is also used by other astronomers, was to change the shape of the telescope mirrors to remove light distortion created by the Earth's atmosphere. The other method they used, which was unique, was to put masks with several holes over most of the telescope mirrors. The combination of these techniques allowed the astronomers to obtain high-quality images that let them see the planet next to the bright star. The star LkCa 15--the planet is named after its star--was the team's second target. They immediately knew they were seeing something new, so they plan to gather more data on the star.
Answer: know the relationship between planets and their stars
Solution:
The research on younger planets helps scientists _ .