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.

Ex Input:
Context: Energy, or the ability to do work, can exist in many different forms. The photo in Figure 17.8 represents six of the eight different forms of energy that are described in this lesson. The guitarist gets the energy he needs to perform from chemical energy in food. He uses mechanical energy to pluck the strings of the guitar. The stage lights use electrical energy and give off both light energy and thermal energy, commonly called heat. The guitar also uses electrical energy, and it produces sound energy when the guitarist plucks the strings. For an introduction to all these forms of energy, go to this URL: . For an interactive animation about the different forms of energy, visit this URL: After you read below about different forms of energy, you can check your knowledge by doing the drag and drop quiz at this URL: . Mechanical energy is the energy of an object that is moving or has the potential to move. It is the sum of an objects kinetic and potential energy. In Figure 17.9, the basketball has mechanical energy because it is moving. The arrow in the same figure has mechanical energy because it has the potential to move due to the elasticity of the bow. What are some other examples of mechanical energy? Energy is stored in the bonds between atoms that make up compounds. This energy is called chemical energy, and it is a form of potential energy. If the bonds between atoms are broken, the energy is released and can do work. The wood in the fireplace in Figure 17.10 has chemical energy. The energy is released as thermal energy when the wood burns. People and many other living things meet their energy needs with chemical energy stored in food. When food molecules are broken down, the energy is released and may be used to do work. Electrons are negatively charged particles in atoms. Moving electrons have a form of kinetic energy called electrical energy. If youve ever experienced an electric outage, then you know how hard it is to get by without electrical energy. Most of the electrical energy we use is produced by power plants and arrives in our homes through wires. Two other sources of electrical energy are pictured in Figure 17.11. The nuclei of atoms are held together by powerful forces. This gives them a tremendous amount of stored energy, called nuclear energy. The energy can be released and used to do work. This happens in nuclear power plants when nuclei fission, or split apart. It also happens in the sun and other stars when nuclei fuse, or join together. Some of the suns energy travels to Earth, where it warms the planet and provides the energy for photosynthesis (see Figure The atoms that make up matter are in constant motion, so they have kinetic energy. All that motion gives matter thermal energy. Thermal energy is defined as the total kinetic energy of all the atoms that make up an object. It depends on how fast the atoms are moving and how many atoms the object has. Therefore, an object with more mass has greater thermal energy than an object with less mass, even if their individual atoms are moving at the same speed. You can see an example of this in Figure 17.13. Energy that the sun and other stars release into space is called electromagnetic energy. This form of energy travels through space as electrical and magnetic waves. Electromagnetic energy is commonly called light. It includes visible light, as well as radio waves, microwaves, and X rays (Figure 17.14). The drummer in Figure 17.15 is hitting the drumheads with drumsticks. This causes the drumheads to vibrate. The vibrations pass to surrounding air particles and then from one air particle to another in a wave of energy called sound energy. We hear sound when the sound waves reach our ears. Sound energy can travel through air, water, and other substances, but not through empty space. Thats because the energy needs particles of matter to pass it on. Energy often changes from one form to another. For example, the mechanical energy of a moving drumstick changes to sound energy when it strikes the drumhead and causes it to vibrate. Any 
 Question: energy of an object that is moving or has the potential to move

Ex Output:
mechanical energy


Ex Input:
Context: One day Mr. White gave his wife ten pounds for her birthday -- ten new pound notes. So Mrs. White went out shopping. She waited for a bus, got on it and sat down next to an o1d 1ady. After a while, Mrs. White noticed that the old 1ady's handbag was open. Inside it, she saw a wad of pound notes exactly like the ones her husband had given her. So she quickly looked into her own bag -- the notes had gone! Mrs. White was sure that the o1d lady next to her had stolen them. She immediately thought of calling the police. But as she disliked making a fuss , she decided to take back the money from the old 1ady's hand bag and say nothing about it. She looked around to make sure nobody was watching. Then she carefully put her hand into the o1d lady's bag, took the notes, and put them into her own handbag. When she got home that evening, Mrs. White showed her husband the beautiful hat she had bought. "How did you pay for it?" Mr. White asked. "With the money you gave me for my birthday, of course" she answered. "Oh? What's that, then?" he asked, as he pointed to a wad of pound notes on the table. 
 Question: What did Mrs. White use the money given by her husband for?

Ex Output:
nothing.


Ex Input:
Context: The story is not linked to the first part of the series. Instead, it focuses on a fictional explanation for the Ryanggang explosion in 2004, in which an unexplained mushroom cloud occurred in North Korea. After reconnaissance satellites detect a large, three-stage Topol intercontinental ballistic missile carrying a nuclear weapon in North Korea, which can strike anywhere in the continental United States, a fictional United States President Adair T. Manning (Peter Coyote) orders a team of U.S. Navy SEALs to destroy the missile and the launch site. The team is led by Lieutenant Robert James (Nicholas Gonzalez). The Pentagon aborts the mission after it receives new information, but by the time the abort order is sent, two SEALs have already parachuted into North Korean territory. James stops the third SEAL from deploying, accidentally knocking the man's helmet against the status indicator mounted near the door. The lieutenant steps onto the makeshift ramp to peer outside, returning to the doorway to inform the rest of men of the abort. The high-speed winds from outside rip the indicator loose and send it flying into the lieutenant's face. Stumbling backwards, James loses his balance and is sucked out of the plane. Callaghan disobeys orders to stand fast, strikes his commanding officer, and follows the first three, taking a radio with him. When North Korean forces led by Commander Hwang (Joseph Steven Yang) find the SEALs, two of the Navy SEALs are killed in a gun battle, and James and Callaghan are captured and tortured by Hwang and his men. After South Korean special forces rescue James and Callaghan, President Manning and the South Korean government send the SEALs and South Korean special forces to destroy the missile site. But after losing radio contact with the SEALs, the President and his top advisers believe that they have been captured again. Under pressure from his military advisor, General Norman Vance (Bruce McGill), the President decides to send B-2 stealth bombers to destroy the site, which would start a full-scale war against North Korea. The SEALs and the South Korean special forces are almost recaptured by Hwang, but he is shot by a defecting officer. James and the South Koreans destroy the missile silo with a bomb before the bombers reach the missile site, which averts the bombing and prevents a full-scale war. A tribunal convicts Callaghan of striking an officer (1 year) and disobeying an officer (10 years). Due to the "black op" nature of the mission, the transcript of the hearing is deemed classified and the charges are expunged from his record, leaving him free to return to his family. Meanwhile, James meets the president in a classified meeting, bringing his mentor Master Chief Scott Boytano (Keith David) as witness to James' receiving of an award. The film closes with Boytano telling James he wasn't red flagged because Boytano had never seen anyone who desired so badly as James did to be a SEAL. During the credits there is a news report on the Ryanggang explosion. 
 Question: Who leads the Navy SEAL team?

Ex Output:

commander hwang