Problem: 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: "How do objects interact under gravity?"

Answer: "Any object exerts gravity on other objects no matter how small it is, and the more matter an object has, the more gravity it has."

OPTIONS:
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- yes
Answer: yes

Problem: Bin Laden and his aides did not need a very large sum to finance their planned attack on America. The 9/11 plotters eventually spent somewhere between $400,000 and $500,000 to plan and conduct their attack. Consistent with the importance of the project, al Qaeda funded the plotters. KSM provided his operatives with nearly all the money they needed to travel to the United States, train, and live. The plotters' tradecraft was not especially sophisticated, but it was good enough. They moved, stored, and spent their money in ordinary ways, easily defeating the detection mechanisms in place at the time. The origin of the funds remains unknown, although we have a general idea of how al Qaeda financed itself during the period leading up to 9/11. General Financing As we explained in chapter 2, Bin Laden did not fund al Qaeda through a personal fortune and a network of businesses in Sudan. Instead, al Qaeda relied primarily on a fund-raising network developed over time. The CIA now estimates that it cost al Qaeda about $30 million per year to sustain its activities before 9/11 and that this money was raised almost entirely through donations. For many years, the United States thought Bin Laden financed al Qaeda's expenses through a vast personal inheritance. Bin Laden purportedly inherited approximately $300 million when his father died, and was rumored to have had access to these funds to wage jihad while in Sudan and Afghanistan and to secure his leadership position in al Qaeda. In early 2000, the U.S. government discovered a different reality: roughly from 1970 through 1994, Bin Laden received about $1 million per year-a significant sum, to be sure, but not a $300 million fortune that could be used to fund jihad. Then, as part of a Saudi government crackdown early in the 1990s, the Bin Laden family was forced to find a buyer for Usama's share of the family company in 1994. The Saudi government subsequently froze the proceeds of the sale. This action had the effect of divesting Bin Laden of what otherwise might indeed have been a large fortune. Nor were Bin Laden's assets in Sudan a source of money for al Qaeda. When Bin Laden lived in Sudan from 1991 to 1996, he owned a number of businesses and other assets.

Question: "What did U.S. government erroneously believe about Bin Laden's ji-had?"

Answer: "Bin Laden received about $1 million per year-a significant sum"

OPTIONS:
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- yes
Answer: no

Problem: Alien Planet starts out with an interstellar spacecraft named Von Braun , leaving Earth's orbit . Traveling at 20 % the speed of light , it reaches Darwin IV in 42 years . Upon reaching orbit , it deploys the Darwin Reconnaissance Orbiter , Which looks for potential landing sites for the probes . The first probe , Balboa , explodes along with its lifting body transport during entry , because one of its wings failed to unfold . Two backup probes , Leonardo da Vinci and Isaac Newton , successfully land on the planet , and learn much about its bizarre indigenous lifeforms , including an apparently sapient species . The robotic probes sent out to research on Darwin IV are called Horus Probes . Each Horus probe consists of an { { convert } } long inflatable , hydrogen-filled balloon , Which is covered with solar receptors , a computer ' brain ' , a ' head ' covered with sensors , and several smaller robots that can be sent to places too dangerous for the probes themselves . The probes have a limited degree of artificial intelligence , very similar to the ' processing power ' of a 4-year-old . All the real thinking is done by a supercomputer in the orbiting Von Braun . The probes are programmed with different personalities ; Ike is more cautious , while Leo is the risk-taker . The two probes are also equipped with a holographic message that will be projected to any sentient life found on Darwin . After the two probes inflate their gas-bags , they encounter a voracious Arrowtongue and watch it pursue a Gyrosprinter .

Question: "What forms of artificial intelligence is used on the spacecraft?"

Answer: "Robots and supercomputers"

OPTIONS:
- no
- yes
Answer:
no