Energy is stored in chemical compounds. This energy is called chemical energy. Chemical energy is a form of potential energy. When bonds between atoms are broken, energy is released. The wood in fireplaces has chemical energy. The energy is released as heat and light when the wood burns. Most living things get their energy from food. When food molecules are broken down, the energy is released. It may then be used to do work, like playing ball or studying science. If you have ever heard, "Eat a good breakfast", thats why. You need energy to do things during the day. To do those things you need energy. You get your energy from the food you eat. That energy is stored in your body until you need it. How did you get to school today? If you walked, you used chemical energy from the food you ate. What if you rode the bus or were driven in a car? Where did that energy come from?

Question: "When energy is released as heat and light from wood, what happens to the atoms in the wood?"

Response: "They are broken down"

A: yes

Sound waves are mechanical waves. They can travel only through matter. They cannot travel through empty space. This was demonstrated in the 1600s by a scientist named Robert Boyle. Boyle placed a ticking clock in a sealed glass jar. The clock could be heard ticking through the air and glass of the jar. Then Boyle pumped the air out of the jar. The clock was still running, but the ticking could not be heard. Thats because the sound couldnt travel without air particles to transfer the sound energy. Is there any other place where sound cannot be heard? Here is a hint: is there any other place that does not have air molecules? Thats right, in space sound cannot be transferred. So can astronauts hear each other? Yes, they can, because they are in enclosed space stations or pressurized suits.In both cases, they are surrounded by air molecules. If they left their space ship and did not use their electronics, they would not be able to hear each other. Next time you watch a science fiction movie, think about this factoid. When spaceships are destroyed by hostile alien beings, there would be no sound heard. Sound waves can travel through many kinds of matter.

Question: "How did Robert Boyle prove how sound waves travel?"

Response: "an explosion under water"

A: no

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: "Whose father was expelled from Yemen?"

Response: "Nashiri's cousin"

A:
no