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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: The Sieferts are the kind of environmentally conscious family who has solar panels atop their home. They use timers on their kids' showers and have planted drought-tolerant landscaping. But they feel kind of guilt. "I haven't thought about the pool as much as I probably should," said Annette Siefert. As California's drought worsens, swimming pools have become a target for those who think the classic backyard greens waste water. Some water districts have banned new pools from being filled and have limited how much water existing pools can use. But some of those agencies are walking back the rules as they make a surprising discovery: Pools aren't the water wasters some have made them out to be. Analyses by various water districts, along with scientific studies, conclude that pools and their surrounding landscapes use about the same amount of water as a lawn of the same size. Over time, pools might even use less water. With pool covers, experts say water evaporation can be cut by almost half, making pools significantly less wasteful than grass and about as efficient as drought-tolerant landscaping. Facing complaints over a recent ban on filling pools, the Santa Margarita Water District conducted its own water-use analysis. It found that pools require thousands of gallons of water to fill initially, but they use about 8,000 gallons less water than a traditional landscape after that. By the third year, the analysis found, the savings add up, and a pool's cumulative water use falls below that of a lawn. Water agencies such as the Los Angeles Department of Water and Power have come to similar conclusions. Armed with new information, Santa Margarita Water District officials will reconsider their ban next week. "We want to respect the people's rights to use their property. There are many families we know that have saved for pools," said Jonathan Volzke, spokesman for the 155,000-customer district. "But at the same time, the reality around us is that we're in the third year of a serious drought, and we don't know if we're in the third year of a three-year drought or the third year of a 10-year drought."
Answer: the water-use of their swimming pool
Solution:
Annette Siefert feels guilty mainly because of _ .