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".

[Q]: Clarifying the Record The defense of U.S. airspace on 9/11 was not conducted in accord with preexisting training and protocols. It was improvised by civilians who had never handled a hijacked aircraft that attempted to disappear, and by a military unprepared for the transformation of commercial aircraft into weapons of mass destruction. As it turned out, the NEADS air defenders had nine minutes' notice on the first hijacked plane, no advance notice on the second, no advance notice on the third, and no advance notice on the fourth. We do not believe that the true picture of that morning reflects discredit on the operational personnel at NEADS or FAA facilities. NEADS commanders and officers actively sought out information, and made the best judgments they could on the basis of what they knew. Individual FAA controllers, facility managers, and Command Center managers thought outside the box in recommending a nationwide alert, in ground-stopping local traffic, and, ultimately, in deciding to land all aircraft and executing that unprecedented order flawlessly. More than the actual events, inaccurate government accounts of those events made it appear that the military was notified in time to respond to two of the hijackings, raising questions about the adequacy of the response. Those accounts had the effect of deflecting questions about the military's capacity to obtain timely and accurate information from its own sources. In addition, they overstated the FAA's ability to provide the military with timely and useful information that morning. In public testimony before this Commission in May 2003, NORAD officials stated that at 9:16, NEADS received hijack notification of United 93 from the FAA. This statement was incorrect. There was no hijack to report at 9:16. United 93 was proceeding normally at that time. In this same public testimony, NORAD officials stated that at 9:24, NEADS received notification of the hijacking of American 77. This statement was also incorrect. The notice NEADS received at 9:24 was that American 11 had not hit the World Trade Center and was heading for Washington, D.C. In their testimony and in other public accounts, NORAD officials also stated that the Langley fighters were scrambled to respond to the notifications about American 77,178 United 93, or both. These statements were incorrect as well. The fighters were scrambled because of the report that American 11 was heading south, as is clear not just from taped conversations at NEADS but also from taped conversations at FAA centers; contemporaneous logs compiled at NEADS, Continental Region headquarters, and NORAD; and other records. <sep>Who handled the U.S. air defense on 9/11?<sep>9
[A]: No

[Q]: So what is gravity? A typical definition of gravity is that it is a force. It causes an attraction between two masses. According to this definition, anything that has mass exerts a force. Any object exerts gravity on other objects. It does not matter how small it is, it has gravity. The more matter an object has, the more gravity it has. Your pencil has a tiny bit of gravity, but far too little to notice. What about a planet? It would have a lot of gravity. An objects gravity exerts a pull on other objects. Friction only occurs between objects that are touching. Gravity can act between objects that are not touching. In fact, gravity can act over very long distances. Where else can you feel gravity? <sep>What does the standard definition of gravity indicate?<sep>Anything that has mass exerts a force of gravity and can exert that force on other objects
[A]: Yes

[Q]: Light rays strike a reflecting surface. They are then reflected back. You can predict the angle of the reflected light. Imagine a ball bouncing off a surface. Light can do the same thing. That is, assuming the surface is shiny. So how do you know where light will go after it strikes a shiny surface? It depends on how the light initially strikes the shiny object. Light does not always go straight toward a surface. Therefore, not all light bounces straight back. Sometimes, light can hit a surface at an angle. The angle at which it strikes the surface tells us how it will bounce off. While light is different to a ball, they react in a similar manner. Many sports rely on knowledge of reflection. Pool players know a lot about reflection. They take great care when they strike the pool ball. They need it to go to a certain place. They know the angle it will hit the side of the pool table. <sep>What sport relies on knowledge of reflection?<sep>Swimming
[A]:
No