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]: We do not know exactly how the hijackers gained access to the cockpit; FAA rules required that the doors remain closed and locked during flight. Ong speculated that they had "jammed their way" in. Perhaps the terrorists stabbed the flight attendants to get a cockpit key, to force one of them to open the cockpit door, or to lure the captain or first officer out of the cockpit. Or the flight attendants may just have been in their way. At the same time or shortly thereafter, Atta-the only terrorist on board trained to fly a jet-would have moved to the cockpit from his business-class seat, possibly accompanied by Omari. As this was happening, passenger Daniel Lewin, who was seated in the row just behind Atta and Omari, was stabbed by one of the hijackers-probably Satam al Suqami, who was seated directly behind Lewin. Lewin had served four years as an officer in the Israeli military. He may have made an attempt to stop the hijackers in front of him, not realizing that another was sitting behind him. The hijackers quickly gained control and sprayed Mace, pepper spray, or some other irritant in the first-class cabin, in order to force the passengers and flight attendants toward the rear of the plane. They claimed they had a bomb. About five minutes after the hijacking began, Betty Ong contacted the American Airlines Southeastern Reservations Office in Cary, North Carolina, via an AT&T airphone to report an emergency aboard the flight. This was the first of several occasions on 9/11 when flight attendants took action outside the scope of their training, which emphasized that in a hijacking, they were to communicate with the cockpit crew. The emergency call lasted approximately 25 minutes, as Ong calmly and professionally relayed information about events taking place aboard the airplane to authorities on the ground. At 8:19, Ong reported:"The cockpit is not answering, somebody's stabbed in business class-and I think there's Mace-that we can't breathe-I don't know, I think we're getting hijacked." She then told of the stabbings of the two flight attendants. At 8:21, one of the American employees receiving Ong's call in North Carolina, Nydia Gonzalez, alerted the American Airlines operations center in Fort Worth, Texas, reaching Craig Marquis, the manager on duty. Marquis soon realized this was an emergency and instructed the airline's dispatcher responsible for the flight to contact the cockpit. At 8:23, the dispatcher tried unsuccessfully to contact the aircraft. <sep>Who jammed their way into the plane's cockpit?<sep>The airline workes
[EX A]: No

[EX Q]: American Airlines Flight 11: FAA Awareness. Although the Boston Center air traffic controller realized at an early stage that there was something wrong with American 11, he did not immediately interpret the plane's failure to respond as a sign that it had been hijacked. At 8:14, when the flight failed to heed his instruction to climb to 35,000 feet, the controller repeatedly tried to raise the flight. He reached out to the pilot on the emergency frequency. Though there was no response, he kept trying to contact the aircraft. At 8:21, American 11 turned off its transponder, immediately degrading the information available about the aircraft. The controller told his supervisor that he thought something was seriously wrong with the plane, although neither suspected a hijacking. The supervisor instructed the controller to follow standard procedures for handling a "no radio" aircraft. The controller checked to see if American Airlines could establish communication with American 11. He became even more concerned as its route changed, moving into another sector's airspace. Controllers immediately began to move aircraft out of its path, and asked other aircraft in the vicinity to look for American 11. At 8:24:38, the following transmission came from American 11: American 11: We have some planes. Just stay quiet, and you'll be okay. We are returning to the airport. The controller only heard something unintelligible; he did not hear the specific words "we have some planes." The next transmission came seconds later: American 11: Nobody move. Everything will be okay. If you try to make any moves, you'll endanger yourself and the airplane. <sep>What were the first things done by America 11 that led the air traffic controller to notify his supervisor that something was wrong with the flight?<sep>There was no response
[EX A]: No

[EX Q]: The bar was manned by an expensive humanoid robot. It turned toward Sarah's wave and acknowledged her with a nod, moments later setting a fluted glass of sparkling liquid in front of her. I marveled at the robot's smoothness and coordination. Clearly, it was a high-end model. Sarah transferred the glass to my free hand and pulled me away from the bar for more introductions, with Alexis trailing after us. I spent the evening listening, mostly. Listening and stuffing my face with all the bits of fine food provided. No one minded; Sarah's inner circle was content to fill our circle of couches with plenty of chatter. Ray, a plump man who was grey where he wasn't bald. Zheng, short and dark and lean, with a very intense gaze. He made me a little uncomfortable. Kishori, petite, her hair strung out in a series of braids that reached nearly to her waist. I categorized them based on their appearances, hoping I'd be able to pick them out of the crowd again later. Most of their chatter was meaningless to mestories of day-to-day activities, how so-and-so had been seen in so-and-so's table at lunch and my wasn't that a surprise, and why hadn't the chef concocted this delectable a selection of appetizers for the dance the other night, but of course those rolled meat pastries reminded one of the pastries back on Earth, didn't they, and this was somehow an interesting fact. After the first half-hour, I stopped expending effort to keep names and stories and gossip straight. I wasn't learning anything useful. I could have started asking questions, but I wanted to get my bearings first. Tonight was for observation. I didn't bother trying to seek out a different group of potentially more interesting people, though. They all looked the same: clusters of social butterflies surrounded by the less apt, the hangers-on, the circle with whom the gossip was shared. <sep>Who did Sarah introduce me to?<sep>Ray, Zheng and Khisori
[EX A]:
Yes