Problem: Energy often changes from one form to another. For example, the drummer transfers motion to sound energy. When the moving drumstick strikes the drum head, the drum starts to vibrate. The motion of the vibrating drum head creates the sound you hear. Any form of energy can change into any other form. Frequently, one form of energy changes into two or more different forms. Have you ever sat in front of a campfire? What are two things you notice? The fire creates light. It is also warm by the fire, meaning it creates heat. The energy of the fire comes from the stored energy in the wood. The wood contains chemical energy. As it burns, the chemical energy is changed into light and heat. Not all chemical energy changes produce light and heat. Our cars use gasoline as a fuel. Gasoline contains chemical energy. When our cars burn gasoline in their engines, it is converted into motion and heat. When energy changes forms, energy is conserved.

Question: "What form of stored energy fuels a fire?"

Answer: "Chemical energy"

OPTIONS:
- no
- yes
Answer: yes

Question:
According to the radar reconstruction, American 77 reemerged as a primary target on Indianapolis Center radar scopes at 9:05, east of its last known position. The target remained in Indianapolis Center's airspace for another six minutes, then crossed into the western portion of Washington Center's airspace at 9:10. As Indianapolis Center continued searching for the aircraft, two managers and the controller responsible for American 77 looked to the west and southwest along the flight's projected path, not east-where the aircraft was now heading. Managers did not instruct other controllers at Indianapolis Center to turn on their primary radar coverage to join in the search for American 77. In sum, Indianapolis Center never saw Flight 77 turn around. By the time it reappeared in primary radar coverage, controllers had either stopped looking for the aircraft because they thought it had crashed or were looking toward the west. Although the Command Center learned Flight 77 was missing, neither it nor FAA headquarters issued an all points bulletin to surrounding centers to search for primary radar targets. American 77 traveled undetected for 36 minutes on a course heading due east for Washington, D.C. By 9:25, FAA's Herndon Command Center and FAA headquarters knew two aircraft had crashed into the World Trade Center. They knew American 77 was lost. At least some FAA officials in Boston Center and the New England Region knew that a hijacker on board American 11 had said "we have some planes." Concerns over the safety of other aircraft began to mount. A manager at the Herndon Command Center asked FAA headquarters if they wanted to order a "nationwide ground stop." While this was being discussed by executives at FAA headquarters, the Command Center ordered one at 9:25. The Command Center kept looking for American 77. At 9:21, it advised the Dulles terminal control facility, and Dulles urged its controllers to look for primary targets. At 9:32, they found one. Several of the Dulles controllers "observed a primary radar target tracking eastbound at a high rate of speed" and notified Reagan National Airport. FAA personnel at both Reagan National and Dulles airports notified the Secret Service. After reading the above, is "Less than 10 minutes" the correct answer to the question "How long did American 77 stay on the Indianapolis Center Radar?"? OPTIONS:
- no
- yes

Answer:
yes

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.
"At what time did the last normal contact between United 93 and the FAA?" is "9:41"?

OPTIONS:
- no
- yes
Output: no

Input: Early in chapter 5 we introduced, along with Khalid Sheikh Mohammed, two other men who became operational coordinators for al Qaeda: Khallad and Nashiri. As we explained, both were involved during 1998 and 1999 in preparing to attack a ship off the coast of Yemen with a boatload of explosives. They had originally targeted a commercial vessel, specifically an oil tanker, but Bin Laden urged them to look for a U.S.warship instead. In January 2000, their team had attempted to attack a warship in the port of Aden, but the attempt failed when the suicide boat sank. More than nine months later, on October 12,2000, al Qaeda operatives in a small boat laden with explosives attacked a U.S. Navy destroyer, the USS Cole. The blast ripped a hole in the side of the Cole, killing 17 members of the ship's crew and wounding at least 40. The plot, we now know, was a full-fledged al Qaeda operation, supervised directly by Bin Laden. He chose the target and location of the attack, selected the suicide operatives, and provided the money needed to purchase explosives and equipment. Nashiri was the field commander and managed the operation in Yemen. Khallad helped in Yemen until he was arrested in a case of mistaken identity and freed with Bin Laden's help, as we also mentioned earlier. Local al Qaeda coordinators included Jamal al Badawi and Fahd al Quso, who was supposed to film the attack from a nearby apartment. The two suicide operatives chosen were Hassan al Khamri and Ibrahim al Thawar, also known as Nibras. Nibras and Quso delivered money to Khallad in Bangkok during Khallad's January 2000 trip to Kuala Lumpur and Bangkok. In September 2000, Bin Laden reportedly told Nashiri that he wanted to replace Khamri and Nibras. Nashiri was angry and disagreed, telling others he would go to Afghanistan and explain to Bin Laden that the new operatives were already trained and ready to conduct the attack. Prior to departing, Nashiri gave Nibras and Khamri instructions to execute the attack on the next U.S.warship that entered the port of Aden.
"In September 2000, Bin Laden wanted to replace two people, who was angered by this?" is "Operational Coordinator for Al Qaeda"?

OPTIONS:
- no
- yes
Output:
yes