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".

Example Input: Right after the Pentagon was hit, NEADS learned of another possible hijacked aircraft. It was an aircraft that in fact had not been hijacked at all. After the second World Trade Center crash, Boston Center managers recognized that both aircraft were transcontinental 767 jetliners that had departed Logan Airport. Remembering the "we have some planes" remark, Boston Center guessed that Delta 1989 might also be hijacked. Boston Center called NEADS at 9:41 and identified Delta 1989, a 767 jet that had left Logan Airport for Las Vegas, as a possible hijack. NEADS warned the FAA's Cleveland Center to watch Delta 1989. The Command Center and FAA headquarters watched it too. During the course of the morning, there were multiple erroneous reports of hijacked aircraft. The report of American 11 heading south was the first; Delta 1989 was the second. NEADS never lost track of Delta 1989, and even ordered fighter aircraft from Ohio and Michigan to intercept it. The flight never turned off its transponder. NEADS soon learned that the aircraft was not hijacked, and tracked Delta 1989 as it reversed course over Toledo, headed east, and landed in Cleveland. But another aircraft was heading toward Washington, an aircraft about which NORAD had heard nothing: United 93. United Airlines Flight 93 FAA Awareness. At 9:27, after having been in the air for 45 minutes, United 93 acknowledged a transmission from the Cleveland Center controller. This was the last normal contact the FAA had with the flight. Less than a minute later, the Cleveland controller and the pilots of aircraft in the vicinity heard "a radio transmission of unintelligible sounds of possible screaming or a struggle from an unknown origin." The controller responded, seconds later: "Somebody call Cleveland?"This was followed by a second radio transmission, with sounds of screaming. <sep>What type of plane was the FAA's Cleveland Center asked to watch?<sep>A fighter aircraft
Example Output: No

Example Input: During this time, Alexander adopted some elements of Persian dress and customs at his court, notably the custom of proskynesis, either a symbolic kissing of the hand, or prostration on the ground, that Persians showed to their social superiors. The Greeks regarded the gesture as the province of deities and believed that Alexander meant to deify himself by requiring it. This cost him the sympathies of many of his countrymen, and he eventually abandoned it. A plot against his life was revealed, and one of his officers, Philotas, was executed for failing to alert Alexander. The death of the son necessitated the death of the father, and thus Parmenion, who had been charged with guarding the treasury at Ecbatana, was assassinated at Alexander's command, to prevent attempts at vengeance. Most infamously, Alexander personally killed the man who had saved his life at Granicus, Cleitus the Black, during a violent drunken altercation at Maracanda (modern day Samarkand in Uzbekistan), in which Cleitus accused Alexander of several judgemental mistakes and most especially, of having forgotten the Macedonian ways in favour of a corrupt oriental lifestyle. Later, in the Central Asian campaign, a second plot against his life was revealed, this one instigated by his own royal pages. His official historian, Callisthenes of Olynthus, was implicated in the plot; however, historians have yet to reach a consensus regarding this involvement. Callisthenes had fallen out of favor by leading the opposition to the attempt to introduce proskynesis. <sep>What are the details of the second plot on Alexander's life in the Central Asian campaign?<sep>Instigated by his own royal pages
Example Output: Yes

Example Input: Magnetism is the ability of a material to be attracted by a magnet. It also include the ability for some material to act like a magnet. No doubt youve handled refrigerator magnets. You can see some in Figure 1.28. You probably know they stick to a metal refrigerator. This is what holds your homework up. Maybe your little sisters drawings are hung on the fridge in this manner. Do magnets stick to all materials? Of course not. You have probably checked and they do not stick to other surfaces. They do not stick to wooden doors or glass windows. Wood and glass are not attracted to a magnet. Obviously, only certain materials are attracted to magnets. <sep>What do some magnets stick to?<sep>Metal Refrigerator
Example Output:
Yes