TASK DEFINITION: In this task, you will be presented with a context passage, a question about that paragraph, and a possible answer to that question. The task is to check the validity of the answer. Answer with "Yes" or "No".
PROBLEM: Speed is an important aspect of motion. It is a measure of how fast or slow something moves. To determine speed you must know two things. First, you must know how far something travels. Second, you need to know how long it takes to travel that far. Speed can be calculated using this formula: speed = distance time A familiar example is the speed of a car. In the U.S., this is usually expressed in miles per hour. Think about a trip you and your family made in the car. Maybe the trip covered 120 miles and it took 3 hours. What was the cars speed? speed = 120 mi = 40 mi/h 3h The speed of a car may also be expressed in kilometers per hour (km/h). The SI unit for speed is meters per second (m/s). This is the unit of measure a scientist would use. <sep>How is speed calculated?<sep>Speed = time motion

SOLUTION: No

PROBLEM: Take a look at this train in Figure 1.11. It looks very futuristic. What do you notice about it? Did you notice that the train has no wheels? How can a train have no wheels? It doesn't need wheels. It actually floats, or levitates, just above the track. Magnets enable the train to do this. This is not a normal train. This is a maglev train. The word maglev stands for magnetic levitation. Because it has no wheels, there is no friction. Some magnets hold the train up. Other magnets are used to move the train forward. This train can go very fast. It can reach speeds up to 480 kilometers (300 miles) per hour! Magnets are pretty cool. What exactly is a magnet? How is it able to exert such force? <sep>How does the train work without wheels?<sep>It uses magnets to levitates above the train tracks

SOLUTION: Yes

PROBLEM: Heat supplies the energy that causes motion. The deeper you go into toward the Earths core, the hotter it gets. At the core it is really hot. All that heat tries to rise toward the surface. In the Mantle, the rock is partially melted and is able to move. As it is heated, the material in the mantle moves toward the surface. As the mantle material rises, it cools. When it reaches the Earths crust, it is mostly stopped. A little of the material can break through the surface, but not all. Instead, it begins to move horizontally. The mantle material moves horizontally away from a mid-ocean ridge crest. Toward the surface, the mantle material starts to cool. As it cools it sinks back down into the mantle. These areas are where deep sea trench occur. The material sinks back down to the core. The system operates like a giant conveyor belt. The motion due to heating and cooling is called convection. <sep>Where do sea trenches occur?<sep>Surface

SOLUTION:
No

