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".

[EX Q]: Abrasion is another type of weathering. Like ice wedging, it is a form of mechanical weathering. Like ice wedging, abrasion does not change the rock into another type of rock. With abrasion, one rock or piece of sediment bumps against another rock. Rocks dont normally roll around on their own, so why do they move? There are a couple of reasons a rock may move. Gravity can cause rocks to move. They may roll downhill or fall off a cliff. As they roll down a hill, they bump into each other. Maybe a moving rock hits a rock that is not moving at the bottom of the hill. Moving water causes rocks and sediment to move. Rocks are bounced along the bottom and bump against one another. As they collide, they begin to chip away at each other. Angular rocks become more rounded with each collision. Strong winds cause abrasion. The wind carries sediment. This sediment is thrown against other rocky surfaces by the wind. It is like sand-blasting a rock. <sep>How does gravity cause rocks to move?<sep>They bump into each other
[EX A]: No

[EX Q]: At 8:38, Ong told Gonzalez that the plane was flying erratically again. Around this time Sweeney told Woodward that the hijackers were Middle Easterners, naming three of their seat numbers. One spoke very little English and one spoke excellent English. The hijackers had gained entry to the cockpit, and she did not know how. The aircraft was in a rapid descent. At 8:41, Sweeney told Woodward that passengers in coach were under the impression that there was a routine medical emergency in first class. Other flight attendants were busy at duties such as getting medical supplies while Ong and Sweeney were reporting the events. At 8:41, in American's operations center, a colleague told Marquis that the air traffic controllers declared Flight 11 a hijacking and "think he's [American 11] headed toward Kennedy [airport in New York City]. They're moving everybody out of the way. They seem to have him on a primary radar. They seem to think that he is descending." At 8:44, Gonzalez reported losing phone contact with Ong. About this same time Sweeney reported to Woodward, "Something is wrong. We are in a rapid descent . we are all over the place." Woodward asked Sweeney to look out the window to see if she could determine where they were. <sep>What did Sweeney tell Woodward s/he was alarmed about around 8:44?<sep>Something was wrong
[EX A]: Yes

[EX Q]: Paris, France (CNN) -- Hundreds of French workers, angry about proposed layoffs at a Caterpillar factory, were holding executives of the company hostage Tuesday, a spokesman for the workers said. Caterpillar's French staff say they are angry about a lack of negotiations over layoffs. It is at least the third time this month that French workers threatened with cutbacks have blockaded managers in their offices to demand negotiations. Executives were released unharmed in both previous situations. The latest incident started Tuesday morning at the office of the construction equipment company in the southeastern city of Grenoble. The workers were angry that Caterpillar had proposed cutting more than 700 jobs and would not negotiate, said Nicolas Benoit, a spokesman for the workers' union. They did not want to harm the Caterpillar executives, Benoit told CNN. One hostage was released Tuesday evening leaving workers with four captives inside the Caterpillar building. The released man was a human resources director identified only as Mr. Petit, because he has heart problems, union representative Bernard Patrick told CNN. Petit had a heart attack a few weeks ago, Patrick said. The four others still being held are Nicolas Polutnik, the head of operations; two other executives; and Petit's personal assistant, he said. About 500 employees were also outside the building protesting. <sep>How many people besides Mr. Petit were held hostage?<sep>Nicolas Polutnik, the head of operations; two other executives; and Petit's personal assistant
[EX A]:
Yes