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: Humans did not reach space until the second half of the 20th century. They needed somehow to break past Earths gravity. A rocket moves rapidly in one direction. The device is propelled by particles flying out of it at high speed in the other direction. There are records of the Chinese using rockets in war against the Mongols as early as the 13th century. The Mongols then used rockets to attack Eastern Europe. Early rockets were also used to launch fireworks. Rockets were used for centuries before anyone could explain how they worked. The theory came about in 1687. Isaac Newton (16431727) described three basic laws of motion, now referred to as Newtons Laws of Motion: 1. An object in motion will remain in motion unless acted upon by a force. 2. Force equals mass multiplied by acceleration. 3. To every action, there is an equal and opposite reaction. Which of these three best explains how a rocket works? Newtons third law of motion. When a rockets propulsion pushes in one direction, the rocket moves in the opposite direction, as seen in the Figure 23.12. For a long time, many people believed that a rocket wouldnt work in space. There would be nothing for the rocket to push against. But they do work! Fuel is ignited in a chamber. The gases in the chamber explode. The explosion creates pressure that forces the gases out of one side of the rocket. The rocket moves in the opposite direction, as shown in Figure 23.13. The force pushing the rocket is called thrust. For centuries, rockets were powered by gunpowder or other solid fuels. These rockets could travel only short distances. Around the turn of the 20th century, several breakthroughs took place. These breakthroughs led to rockets that could travel beyond Earth. Liquid fuel gave rockets enough power to escape Earths gravity (Figure 23.14). By using multiple stages, empty fuel containers could drop away. This reduced the mass of the rocket so that it could fly higher. Rockets were used during World War II. The V2 was the first human-made object to travel high enough to be considered in space (Figure 23.15). Its altitude was 176 km (109 miles) above Earths surface. Wernher von Braun was a German rocket scientist. After he fled Germany in WWII, he helped the United States develop missile weapons. After the war, von Braun worked for NASA. He designed the Saturn V rocket (Figure One of the first uses of rockets in space was to launch satellites. A satellite is an object that orbits a larger object. An orbit is a circular or elliptical path around an object. Natural objects in orbit are called natural satellites. The Moon is a natural satellite. Human-made objects in orbit are called artificial satellites. There are more and more artificial satellites orbiting Earth all the time. They all get into space using some sort of rocket. Why do satellites stay in orbit? Why dont they crash into Earth due to the planets gravity? Newtons law of universal gravitation describes what happens. Every object in the universe is attracted to every other object. Gravity makes an apple fall to the ground. Gravity also keeps you from floating away into the sky. Gravity holds the Moon in orbit around Earth. It keeps Earth in orbit around the Sun. Newton used an example to explain how gravity makes orbiting possible. Imagine a cannonball launched from a high mountain, as shown in Figure 23.17. If the cannonball is launched at a slow speed, it will fall back to Earth. This is shown as paths (A) and (B). Something different happens if the cannonball is launched at a fast speed. The Earth below curves away at the same rate that the cannonball falls. The cannonball then goes into a circular orbit, as in path (C). If the cannonball is launched even faster, it could go into an elliptical orbit (D). It might even leave Earths gravity and go into space (E). Unfortunately, Newtons idea would not work in real life. A cannonball launched at a fast speed from Mt. Everest would not go into orbit. 
 Question: The first rocket to travel into space was used during

Ex Output:
world war ii.


Ex Input:
Context: Blood is a liquid connective tissue. It circulates throughout the body via blood vessels due to the pumping action of the heart. You couldnt survive without the approximately 4.5 to 5 liters of blood that are constantly being pumped through your blood vessels. Blood consists of both liquid and cells. The liquid part of blood is called plasma. Plasma is a watery, golden-yellow fluid that contains many dissolved substances. Substances dissolved in plasma include glucose, proteins, and gases. Plasma also contains blood cells. There are three types of blood cells: red blood cells, white blood cells, and platelets. You can see all three types in Figure 18.8. 1. Red blood cells are shaped like flattened disks. There are trillions of red blood cells in your blood. Each red blood cell has millions of molecules of hemoglobin. Hemoglobin is a protein that contains iron. The iron in hemoglobin gives red blood cells their red color. It also explains how hemoglobin carries oxygen. The iron in hemoglobin binds with oxygen molecules so they can be carried by red blood cells. 2. White blood cells are larger than red blood cells, but there are far fewer of them. Their role is to defend the body in various ways. For example, white blood cells called phagocytes engulf and destroy microorganisms and debris in the blood. 3. Platelets are small, sticky cell fragments that help blood clot. A blood clot is a solid mass of cell fragments and other substances that plugs a leak in a damaged blood vessel. Platelets stick to tears in blood vessels and to each other, helping to form a clot at the site of injury. Platelets also release chemicals that are needed for clotting to occur. The main function of blood is transport. Blood in arteries carries oxygen and nutrients to all the bodys cells. Blood in veins carries carbon dioxide and other wastes away from cells to be excreted. Blood also transports the chemical messengers called hormones to cells throughout the body where they are needed to regulate body functions. Blood has several other functions as well. For example, blood: defends the body against infections. repairs body tissues. controls the bodys pH. helps regulate body temperature. Red blood cells carry proteins called antigens on their surface. People may vary in the exact antigens their red blood cells carry. The specific proteins are controlled by the genes they inherit from their parents. The particular antigens you inherit determine your blood type. Why does your blood type matter? Blood type is important for medical reasons. A patient cant safely receive a transfusion of blood containing antigens not found in the patients own blood. With foreign antigens, the transfused blood will be rejected by the persons immune system. This causes a reaction in the patients bloodstream, called agglutination. The transfused red blood cells clump together, as shown in Figure 18.9. The clumped cells block blood vessels and cause other life-threatening problems. There are many sets of antigens that determine different blood types. Two of the best known are the ABO and Rhesus antigens. Both are described below. You can also learn more about them by watching this video: ABO blood type is determined by two common antigens, often called antigen A and antigen B. If your red blood cells carry only antigen A, you have blood type A. If your red blood cells carry only antigen B, you have blood type B. If your red blood cells carry both antigen A and antigen B, you have blood type AB. If your red blood cells carry neither antigen A nor antigen B, you have blood type O. Another red blood cell antigen determines a persons Rhesus blood type. This blood type depends on a single common antigen, typically referred to as the Rhesus (Rh) antigen. If your red blood cells carry the Rhesus antigen, you have Rhesus-positive blood, or blood type Rh+. If your red blood cells lack the Rhesus antigen, you have Rhesus-negative blood, or blood type Rh-. Some diseases affect mainly the blood or its components. They include anemia, leukemia, hemophilia, and sickle- cell disease. Anemia is a disease that occurs when there is not enough hemoglobin 
 Question: __genetic disorder in which abnormal hemoglobin causes red blood cells to change shape

Ex Output:
sickle- cell disease


Ex Input:
Context: Hoping to rebound from a divisional home loss to the Eagles, the Cowboys flew to Bank of America Stadium for a Week 16 Saturday night duel with the Carolina Panthers. In the first quarter, Dallas shot first with QB Tony Romo completing a 10-yard TD pass to WR Terrell Owens for the only score of the period. In the second quarter, the 'Boys continued their assault as RB Marion Barber got a 5-yard TD run. The Panthers would get on the board with QB Matt Moore completing an 11-yard TD pass to WR Steve Smith. The Cowboys end the half with rookie kicker Nick Folk getting a 42-yard field goal. In the third quarter, Carolina started to try a comeback as kicker John Kasay getting a 37-yard field goal for the only score of the period. In the fourth quarter, Dallas would respond with Folk kicking a 23-yard field goal. The Panthers tried to rally as Kasay nailing a 25-yard field goal, yet the 'Boys were able to hold off every possible attempt. With the win, the Cowboys improved to 13-2 and clinched homefield through NFC Playoffs with Green Bay's loss to Chicago on Sunday. Terrell Owens (5 receptions for 48 yards and 1 touchdown) left the game in the second quarter with a high left ankle sprain. 
 Question: Who caught the longest touchdown pass?

Ex Output:

steve smith