Input: When land is cleared, habitats are lost. It may be cleared for agriculture. It may also be used for building new homes or businesses. Within the past 100 years, the amount of land used for agriculture has almost doubled. Land used for grazing cattle has more than doubled. Many wetlands have also been lost to agriculture. The U.S. has lost almost all the natural tall-grass prairies. Thee areas of tall thick grass have virtually disappeared. These areas of land had thick fertile soil. Their grasses had very deep root systems. These deep and thick roots reduced the amount of soil erosion. They also were home to many plants and animals. Prairies were wonderful places. They were home to colorful flowers, prairie dogs, and herds of bison.
"Why do we clear land?" is "For new homes"?

OPTIONS:
- no
- yes
Output: yes

Input: You may wonder if there are other examples of static discharge. The answer is yes. Lightning is a form of static discharge. It is much more dramatic than what happens between you and the door knocker, but it is the same principle. You can see how it occurs in the following diagram and animation. You have no doubt seen lightning in a rainstorm. What does lighting have to do with static electricity? As it turns out, everything! During a rainstorm, clouds develop regions of different charges. This happens due to the movement of air molecules, water drops, and ice particles. The negative charges are concentrated at the base of the clouds. The positive charges are concentrated at the top. The negative charges repel electrons on the ground below. The ground then becomes positively charged. Over time the differences increase. Eventually the electrons are discharged. This is what we see as lightning. You can watch an awesome slow-motion lightning strike below.

Does the response "Because of motion present in air molecules, water drops, and ice particles" correctly answer the question "How can different regions of clouds have different charges?"?

OPTIONS:
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- yes
***
Output: yes

(CNN) -- Cuba will pardon more than 2,900 prisoners, the government said Friday, though U.S. subcontractor Alan Gross is not among those who will be freed. The decision to release the prisoners follows "numerous requests" from their family members and religious institutions, and is a humanitarian gesture, said Cuban President Raul Castro. Among those who might be freed are prisoners over the age of 60, along with those who are sick, female or young with no previous criminal record. With some exceptions, prisoners convicted of spying, terrorism, murder and drug trafficking will not be released. Those who will be freed have already served a "important" part of their sentences and exhibited good behavior, according to an official statement published on the state-run website Cubadebate. The jailed American, Gross, will not be among those pardoned, the Cuban Interests Section in Washington said. Gross was jailed in December 2009, when he was working as a subcontractor on a U.S. Agency for International Development project aimed at spreading democracy. Castro has accused him of importing satellite equipment to connect dissidents to the Internet, and this year Cuba's highest court upheld the 15-year sentence imposed on Gross for committing crimes against the security of the state. He has maintained his innocence and said he was trying to help connect the Jewish community to the Internet. Castro, speaking to the National Assembly, said that 86 prisoners from 25 countries would be among those released in coming days. He cited the upcoming visit of Pope Benedict XVI as one of the motivations behind the move, which he said showed the "generosity and strength of the revolution." The pope has said he plans to visit Mexico and Cuba before Easter.

Question: "Of the 2,900 prisoners, who will not be released?"

OPTIONS:
- no
- yes

Answer: "Terrorists"

Response: yes

Fossils may form in other ways. Fossils can be preserved almost completely. In this process, the organism doesnt change much. As seen below, tree sap may cover an organism. With time, the sap hardens. It turns to into amber. The original organism is preserved. This is very exciting for scientists. They are able to study the DNA of the organism that no longer lives on Earth. Some animals have been found frozen in ice. Others have been found in tar pits after falling in. Molds and casts are another way organisms can be fossilized. Have you ever walked in soft mud and left footprints? Once in a while, these traces of organisms can be preserved. In this case, nothing is left of the organism. A mold is an imprint of an organism that is preserved in rock. The organisms remains break down completely. There is nothing left of the original plant and animal.

Question: "What can scientists study about a fossil found in amber, that they normally cannot with most fossils?"

Response: "The atomic breakdown"
OPTIONS:
- no
- yes

A: no

Problem: 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 do sound waves travel?"

Answer: "through space"

OPTIONS:
- no
- yes
Answer: no

Problem: As food is pushed along, it undergoes digestion. Digestion is the process of breaking down food into nutrients. There are two types of digestion: mechanical digestion and chemical digestion. Mechanical digestion occurs when large chunks are turned into smaller chucks. Perhaps not surprisingly, this happens when you chew your food. Once you swallow the food, your stomach also does some of this work. Chemical digestion occurs when food is broken down into useful nutrients. This is a chemical process that begins as you start to chew your food. The saliva in your mouth starts this process. Once you swallow, the acid in your stomach further breaks down food. From the stomach, the foods moves into the small intestine. In the small intestines, another set of chemicals goes to work. Are you surprised? Your small intestine, and not your stomach, does most of the work!

Question: "What organs help digestion?"

Answer: "Mouth"

OPTIONS:
- no
- yes
Answer:
yes