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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: Last year, CCTV journalists approached pedestrians with their cameras, held a microphone to their mouth and asked a simple question, "Are you happy?" The question has caught many interviewees off guard. Even Mo Yan, who just won a Nobel Prize, responded by saying, "I don't know". While the question has become a buzz phrase and the Internet plays host to heated discussions, we ask: What exactly is happiness? And how do you measure it? In the 1776 US Declaration of Independence, Thomas Jefferson set in writing the people's unalienable right to "Life, Liberty and the Pursuit of Happiness". 235 years on, Wen Jiabao told the nation, "Everything we do is aimed at letting people live more happily." At National People's Congress, officials agreed that increasing happiness would be a top target for the 12th five-year plan. US psychologist Ed Diener, author of Happiness: Unlocking the Mysteries of Psychological Wealth, describes happiness as " a combination of life satisfaction and having more positive than negative emotions", according to US broadcasting network PBS. This may sound straightforward enough, but it still doesn't explain what determines people's happiness. Many argue that happiness is _ and that there is no single source. It also means different things to different people. For some, happiness can be as simple as having enough cash. Researchers believe happiness can be separated into two types: daily experiences of hedonic well-being; and evaluative well-being, the way people think about their lives as a whole. The former refers to the quality of living, whereas the latter is about overall happiness, including life goals and achievements. Happiness can cross both dimensions. Li Jun, a psychologist and mental therapy practitioner at a Beijing clinic, says, "Happiness can mean both the most basic human satisfaction or the highest level of spiritual pursuit. It's a simple yet profound topic." Chen Shangyuan, 21, a junior English major at Nanjing University of Aeronautics and Astronautics, said his idea of happiness always evolves. "At present it relates to how productive I am in a day," he said. "It might be linked to job security or leisure time after I graduate." Then there is the question of measuring happiness. Does it depend on how many friends we have, or whether we own the latest smart phone? Is it even quantifiable? Economists are trying to measure happiness in people's lives. Since 1972, Bhutan's GDP measurement has been replaced by a Gross National Happiness index. It is calculated according to the peoples' sense of being well-governed, their relationship with the environment, their satisfaction with economic development, and their sense of national belonging. In 2009, US economist Joseph Stiglitz proposed "to shift emphasis from measuring economic production to measuring people's well-being". But is well-being more easily measured?
Answer: people's happiness is an important target for the development of a country
Solution:
From what Thomas Jefferson and Wen Jiabao mentioned in the passage, we know _ .