Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Example Input: Context: The movie opens with Ralph Wiggum singing along to the 20th Century Fox logo. We then cut to Itchy & Scratchy: The Movie. They are out on the moon. Itchy kills Scratchy and then returns to earth and is painted as a hero by the media. Shortly thereafter, Itchy is elected president. Later as Itchy is in the White House, he sees a supposedly dead Scratchy on the moon. Scratchy holds up a sign that says "I'm telling", which freaks President Itchy out. Itchy then retaliates by sending a hundred missiles toward Scratchy. This is then seen in the theater which is being attended by the Simpsons. Homer stands up and yells "Boring!". Lisa replies "Dad, we can't see the movie!". Homer then goes off on a tirade about why they're paying to watch something in the theater that they normally watch on TV, and that everyone in the audience is a gigantic sucker, especially you. Cue a very fancy and stylized version of the standard Simpsons opening theme.The opening ends with Green Day hosting a concert at Lake Springfield (Singing the Simpsons theme after the opening credits). After they finish their song, they talk about the environment. The audience becomes angry and begins to throw garbage at them polluting the lake and causing their barge to dissolve and sink, killing them. The next day at church, while they have a short memorial for Green Day, Grampa is possessed by God warns the city of a future disaster. Marge believes Grampa's prediction, and decides to work out the meaning of the message. Meanwhile, Lisa starts to talk about the environment, with no success. She encounters Colin, an Irish boy who shares the same passions as her. Homer gets a note from Marge of his chores, and one is fixing the sinkhole. Instead of fixing it, Homer puts Maggie's sandbox over it. His next chore is to fix the roof. While repairing the roof, Homer and Bart decide to have a dare contest. Homer dares Bart to climb the antenna. Bart does so, and gets stuck. Homer shakes it in order to get Bart down. Homer dares Bart to skateboard to Krusty Burger naked, which Bart object's to, saying girls will see his "doodle". After Homer threatens to call him chicken for the rest of his life, Bart agrees. Bart becomes stuck naked on the window of the building. After he is apprehended by the police, and tied to a Stop sign pole, Homer turns up and they decide to order a meal, he brings him socks and a shirt, and no pants. Inside the restuarant, Ned Flanders helps Bart out by giving him a pair of pants, and understands his feelings which begins a relationship and mutual respect between the two. Meanwhile Krusty is filming a commercial. When recording finishes Krusty orders for the pig he is using in the commercial to be slaughtered, causing it to flee to Homer who adopts him, and calls him Spider-Pig. That evening Lisa holds a conference at city hall, called "An Irritating Truth" and explains that the town lake cannot sustain anymore pollution. Mayor Quimby declares a state of emergency and orders the cleansing and protection of Lake Springfield.They put up a fence around the lake to halt further dumping, and announce it is idiot proof, using Cletus as an example to try to throw a possum in the lake, and fail. Soon, Marge asks Homer where "Spider-Pig's/Harry Plopper's" waste is going. Homer shows her an overflowing silo, asking how a pig can fill it up in two days, Homer replies that he helped, horrifying Marge who tells Homer to dispose of it safely. While waiting in a queue at the dump Homer is told by Lenny that Lard Lad Donuts has been shut down and that they are giving away free donuts. Homer, in his haste to get to the giveaway decides on a quicker means of disposal and dumps the silo into the lake, causing it to become heavily polluted. A nearby squirrel jumps into it and becomes severely mutated, with many eyes. Nearby,
Question: What do Lisa and Colin convince the entire town to clean?
Example Output: the lake

Example Input: Context: Energy from the Sun comes from the lightest element, hydrogen, fusing together to create the second lightest element, helium. Nuclear fusion on the Sun releases tremendous amounts of solar energy. The energy travels to the Earth, mostly as visible light. The light carries the energy through the empty space between the Sun and the Earth as radiation. Solar energy has been used for power on a small scale for hundreds of years, and plants have used it for billions of years. Unlike energy from fossil fuels, which almost always come from a central power plant or refinery, solar power can be harnessed locally (Figure 1.1). A set of solar panels on a homes rooftop can be used to heat water for a swimming pool or can provide electricity to the house. Societys use of solar power on a larger scale is just starting to increase. Scientists and engineers have very active, ongoing research into new ways to harness energy from the Sun more efficiently. Because of the tremendous amount of incoming sunlight, solar power is being developed in the United States in southeastern California, Nevada, and Arizona. Solar panels supply power to the Interna- tional Space Station. Solar power plants turn sunlight into electricity using a large group of mirrors to focus sunlight on one place, called a receiver (Figure 1.2). A liquid, such as oil or water, flows through this receiver and is heated to a high temperature by the focused sunlight. The heated liquid transfers its heat to a nearby object that is at a lower temperature through a process called conduction. The energy conducted by the heated liquid is used to make electricity. This solar power plant uses mirrors to focus sunlight on the tower in the center. The sunlight heats a liquid inside the tower to a very high temperature, producing energy to make electricity. Solar energy has many benefits. It is extremely abundant, widespread, and will never run out. But there are problems with the widespread use of solar power. Sunlight must be present. Solar power is not useful in locations that are often cloudy or dark. However, storage technology is being developed. The technology needed for solar power is still expensive. An increase in interested customers will provide incentive for companies to research and develop new technologies and to figure out how to mass-produce existing technologies (Figure 1.3). Solar panels require a lot of space. Fortunately, solar panels can be placed on any rooftop to supply at least some of the power required for a home or business. This experimental car is one example of the many uses that engineers have found for solar energy. Click image to the left or use the URL below. URL: Click image to the left or use the URL below. URL:
Question: the source of solar power is nuclear
Example Output: fusion.

Example Input: Context: We are lucky to have an atmosphere on Earth. The atmosphere supports life, and is also needed for the water cycle and weather. The gases of the atmosphere even allow us to hear. Most of the atmosphere is nitrogen, but it doesnt do much. Carbon dioxide and oxygen are the gases in the atmosphere that are needed for life. Plants need carbon dioxide for photosynthesis. They use sunlight to change carbon dioxide and water into food. The process releases oxygen. Without photosynthesis, there would be very little oxygen in the air. Other living things depend on plants for food. These organisms need the oxygen plants release to get energy out of the food. Even plants need oxygen for this purpose. The atmosphere protects living things from the Suns most harmful rays. Gases reflect or absorb the strongest rays of sunlight. Figure 15.1 models this role of the atmosphere. Gases in the atmosphere surround Earth like a blanket. They keep the temperature in a range that can support life. The gases keep out some of the Suns scorching heat during the day. At night, they hold the heat close to the surface, so it doesnt radiate out into space. Figure 15.2 shows the role of the atmosphere in the water cycle. Water vapor rises from Earths surface into the atmosphere. As it rises, it cools. The water vapor may then condense into water droplets and form clouds. If enough water droplets collect in clouds they may fall as rain. This how freshwater gets from the atmosphere back to Earths surface. Without the atmosphere, there would be no clouds or rain. In fact, there would be no weather at all. Most weather occurs because the atmosphere heats up more in some places than others. Weather makes life interesting. Weather also causes weathering. Weathering is the slow wearing down of rocks on Earths surface. Wind-blown sand scours rocks like sandpaper. Glaciers of ice scrape across rock surfaces like a file. Even gentle rain may seep into rocks and slowly dissolve them. If the water freezes, it expands. This eventually causes the rocks to crack. Without the atmosphere, none of this weathering would happen. Sound is a form of energy that travels in waves. Sound waves cant travel through empty space, but they can travel through gases. Gases in the air allow us to hear most of the sounds in our world. Because of air, you can hear birds singing, horns tooting, and friends laughing. Without the atmosphere, the world would be a silent, eerie place. Air is easy to forget about. We usually cant see it, taste it, or smell it. We can only feel it when it moves. But air is actually made of molecules of many different gases. It also contains tiny particles of solid matter. Figure 15.3 shows the main gases in air. Nitrogen and oxygen make up 99 percent of air. Argon and carbon dioxide make up much of the rest. These percentages are the same just about everywhere in the atmosphere. Air also includes water vapor. The amount of water vapor varies from place to place. Thats why water vapor isnt included in Figure 15.3. It can make up as much as 4 percent of the air. Ozone is a molecule made of three oxygen atoms. Ozone collects in a layer in the stratosphere. Air includes many tiny particles. The particles may consist of dust, soil, salt, smoke, or ash. Some particles pollute the air and may make it unhealthy to breathe. But having particles in the air is very important. Tiny particles are needed for water vapor to condense on. Without particles, water vapor could not condense. Then clouds could not form and Earth would have no rain. We usually cant sense the air around us unless it is moving. But air has the same basic properties as other matter. For example, air has mass, volume and, of course, density. Density is mass per unit volume. Density is a measure of how closely molecules are packed together. The closer together they are, the greater the density. Since air
Question: third most common gas in Earths atmosphere
Example Output:
argon