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?

Question: "Does size matter as to whether or not an object has gravity?"

OPTIONS:
- no
- yes

Answer: "no"

Response: yes

Our sun and other stars release light energy. At least this is what we see. Our Sun and stars also emit more than just light. Scientists call the type of energy that our Sun and stars release electromagnetic energy. This form of energy travels through space. Electromagnetic energy includes the light we see. It also includes much more. Many of these things we know about, but dont always think about. Electromagnetic energy includes radio waves, microwaves, and X rays. We now have devices in our homes and offices that release these same forms of energy. We use electromagnetic energy to make our lives better.

Question: "Where do we use electromagnetic energy to make our lives better?"

Response: "Devices in our homes and offices"
OPTIONS:
- no
- yes

A: yes

Problem: Bin Laden reportedly discussed the planes operation with KSM and Atef in a series of meetings in the spring of 1999 at the al Matar complex near Kandahar. KSM's original concept of using one of the hijacked planes to make a media statement was scrapped, but Bin Laden considered the basic idea feasible. Bin Laden, Atef, and KSM developed an initial list of targets. These included the White House, the U.S. Capitol, the Pentagon, and the World Trade Center. According to KSM, Bin Laden wanted to destroy the White House and the Pentagon, KSM wanted to strike the World Trade Center, and all of them wanted to hit the Capitol. No one else was involved in the initial selection of targets. Bin Laden also soon selected four individuals to serve as suicide operatives: Khalid al Mihdhar, Nawaf al Hazmi, Khallad, and Abu Bara al Yemeni. During the al Matar meetings, Bin Laden told KSM that Mihdhar and Hazmi were so eager to participate in an operation against the United States that they had already obtained U.S. visas. KSM states that they had done so on their own after the suicide of their friend Azzam (Nashiri's cousin) in carrying out the Nairobi bombing. KSM had not met them. His only guidance from Bin Laden was that the two should eventually go to the United States for pilot training. Hazmi and Mihdhar were Saudi nationals, born in Mecca. Like the others in this initial group of selectees, they were already experienced mujahideen. They had traveled together to fight in Bosnia in a group that journeyed to the Balkans in 1995. By the time Hazmi and Mihdhar were assigned to the planes operation in early 1999, they had visited Afghanistan on several occasions. Khallad was another veteran mujahid, like much of his family. His father had been expelled from Yemen because of his extremist views. Khallad had grown up in Saudi Arabia, where his father knew Bin Laden, Abdullah Azzam, and Omar Abdel Rahman (the "Blind Sheikh").

Question: "Where did Mihdhar and Hazmi become experienced mujahideen?"

Answer: "Mecca"

OPTIONS:
- no
- yes
Answer: no

Question:
When American 11 struck the World Trade Center at 8:46, no one in the White House or traveling with the President knew that it had been hijacked. While that information circulated within the FAA, we found no evidence that the hijacking was reported to any other agency in Washington before 8:46. Most federal agencies learned about the crash in New York from CNN. Within the FAA, the administrator, Jane Garvey, and her acting deputy, Monte Belger, had not been told of a confirmed hijacking before they learned from television that a plane had crashed. Others in the agency were aware of it, as we explained earlier in this chapter. Inside the National Military Command Center, the deputy director of operations and his assistant began notifying senior Pentagon officials of the incident. At about 9:00, the senior NMCC operations officer reached out to the FAA operations center for information. Although the NMCC was advised of the hijacking of American 11, the scrambling of jets was not discussed. In Sarasota, Florida, the presidential motorcade was arriving at the Emma E. Booker Elementary School, where President Bush was to read to a class and talk about education. White House Chief of Staff Andrew Card told us he was standing with the President outside the classroom when Senior Advisor to the President Karl Rove first informed them that a small, twin-engine plane had crashed into the World Trade Center. The President's reaction was that the incident must have been caused by pilot error. At 8:55, before entering the classroom, the President spoke to National Security Advisor Condoleezza Rice, who was at the White House. She recalled first telling the President it was a twin-engine aircraft-and then a commercial aircraft-that had struck the World Trade Center, adding "that's all we know right now, Mr. President." At the White House, Vice President Dick Cheney had just sat down for a meeting when his assistant told him to turn on his television because a plane had struck the NorthTower of the World Trade Center. The Vice President was wondering "How the hell could a plane hit the World Trade Center" when he saw the second aircraft strike the South Tower. Elsewhere in the White House, a series of 9:00 meetings was about to begin. In the absence of information that the crash was anything other than an accident, the White House staff monitored the news as they went ahead with their regular schedules. After reading the above, is "46 miutes" the correct answer to the question "What detail about the crash of American 11 did White House Senior Advisor Karl Rove not tell the president?"? OPTIONS:
- no
- yes

Answer:
no

Electric charge is a physical property. It occurs between particles or objects. It causes them to attract or repel each other. They do not even have to touch. This is unlike the typical push or pull you may be familiar with. All electric charge is based on the protons and electrons in atoms. A proton has a positive electric charge. An electron has a negative electric charge. Forces on Charged Objects Most atoms are balanced electrically. They have the same number of positive and negative charges. Therefore, the number of protons equals the number of electrons. Neutrons do not matter as they have no charge. When an object loses some electrons, it becomes positively charged. There are now more protons than electrons inside the atom. The lost electrons may remain free. Or, they may attach to another object. The new object now has more electrons than protons. It then becomes negatively charged.

Question: "Why does an object's charge become positive?"

OPTIONS:
- no
- yes

Answer: "When an object loses some electrons,it becomes positive"

Response:
yes