(CNN) -- Jo-Wilfried Tsonga ended Roger Federer's hopes of winning a record-equaling seventh Wimbledon title on Wednesday as the French 12th seed staged a stunning fightback to reach the semifinals. Federer appeared to be cruising into the last four after winning the first two sets, but Tsonga inflicted the Swiss world No. 3's first defeat from that vantage point in 179 grand slam matches. It was only the third time in the 29-year-old's glittering career that the 16-time grand slam champion had surrendered a two-set lead. Tsonga, ranked 19th in the world, triumphed 3-6 6-7 (3-7) 6-4 6-4 6-4 on Centre Court, serving out to love as he earned a clash with second seed Novak Djokovic. The Serbian, who beat Tsonga in the 2008 Australian Open final, ended the dream run of Australian 18-year-old Bernard Tomic. Tsonga defeated Federer for just the second time in six meetings, their first on grass. "It was amazing. I played unbelievable. It's never easy to come back against Roger. I'm so happy, it's crazy," the 26-year-old told reporters after reaching the semifinals at Wimbledon for the first time. "He's the biggest champion in the sport. He has achieved so much and is the best player in the world. To be two sets down and come back was unbelievable. I served really well. Against Djokovic I will have to come out and do the same again." Federer has now lost in the quarterfinals two years in a row, being beaten by eventual runner-up Tomas Berdych in 2010. "Jo played great. Really from start to finish I don't remember seeing a break point after I broke him in the first game," Federer said.

Question: "Which two players did Roger Federer lose to in consecutive Wimbledon Semifinals matches?"

OPTIONS:
- no
- yes

Answer: "Jo-Wilfried Tsonga and Thomas Berdych"

Response: yes

Assisting Zionist causes Einstein was a figurehead leader in helping establish the Hebrew University of Jerusalem, which opened in 1925, and was among its first Board of Governors. Earlier, in 1921, he was asked by the biochemist and president of the World Zionist Organization, Chaim Weizmann, to help raise funds for the planned university. He also submitted various suggestions as to its initial programs. Among those, he advised first creating an Institute of Agriculture in order to settle the undeveloped land. That should be followed, he suggested, by a Chemical Institute and an Institute of Microbiology, to fight the various ongoing epidemics such as malaria, which he called an "evil" that was undermining a third of the country's development. Establishing an Oriental Studies Institute, to include language courses given in both Hebrew and Arabic, for scientific exploration of the country and its historical monuments, was also important. Chaim Weizmann later became Israel's first president. Upon his death while in office in November 1952 and at the urging of Ezriel Carlebach, Prime Minister David Ben-Gurion offered Einstein the position of President of Israel, a mostly ceremonial post. The offer was presented by Israel's ambassador in Washington, Abba Eban, who explained that the offer "embodies the deepest respect which the Jewish people can repose in any of its sons". Einstein declined, and wrote in his response that he was "deeply moved", and "at once saddened and ashamed" that he could not accept it.

Question: "How did Einstein feel when he had to decline the offer of becoming Israel's president?"

Response: "He passed it on to his sons"
OPTIONS:
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- yes

A: no

Problem: Gravitational Potential Energy is affected by position. Like the leaves on trees, anything that is raised up has the potential to fall. It has potential energy. You can see examples of people with gravitational potential energy in 1.5 Figure below. Gravitational potential energy depends on two things. It depends on its weight, because a large falling rock can do more damage than a leaf falling from a tree. It also depends on its height above the ground. Like the skateboarder, the higher the ramp, the faster he will be going when he reaches the bottom. Like all energy, gravitational potential energy has the ability to do work. In this case, weight has the potential to deliver a force. More important for us is that it has the ability to cause change. What kind of change you may ask? Gravitational potential energy has the ability to cause motion.

Question: "What does gravitational potential energy depend on?"

Answer: "Height and volume of the object"

OPTIONS:
- no
- yes
Answer: no

Zinni feared that Bin Laden would in the future locate himself in cities, where U.S. missiles could kill thousands of Afghans. He worried also lest Pakistani authorities not get adequate warning, think the missiles came from India, RESPONSES TO AL QAEDA'S INITIAL ASSAULTS 135 and do something that everyone would later regret. Discussing potential repercussions in the region of his military responsibility, Zinni said, "It was easy to take the shot from Washington and walk away from it. We had to live there." Zinni's distinct preference would have been to build up counterterrorism capabilities in neighboring countries such as Uzbekistan. But he told us that he could not drum up much interest in or money for such a purpose from Washington, partly, he thought, because these countries had dictatorial governments. After the decision-in which fear of collateral damage was an important factor- not to use cruise missiles against Kandahar in December 1998, Shelton and officers in the Pentagon developed plans for using an AC-130 gunship instead of cruise missile strikes. Designed specifically for the special forces, the version of the AC-130 known as "Spooky"can fly in fast or from high altitude, undetected by radar; guided to its zone by extraordinarily complex electronics, it is capable of rapidly firing precision-guided 25, 40, and 105 mm projectiles. Because this system could target more precisely than a salvo of cruise missiles, it had a much lower risk of causing collateral damage. After giving Clarke a briefing and being encouraged to proceed, Shelton formally directed Zinni and General Peter Schoomaker, who headed the Special Operations Command, to develop plans for an AC-130 mission against Bin Laden's headquarters and infrastructure in Afghanistan. The Joint Staff prepared a decision paper for deployment of the Special Operations aircraft. Though Berger and Clarke continued to indicate interest in this option, the AC-130s were never deployed. Clarke wrote at the time that Zinni opposed their use, and John Maher, the Joint Staff 's deputy director of operations, agreed that this was Zinni's position. Zinni himself does not recall blocking the option. He told us that he understood the Special Operations Command had never thought the intelligence good enough to justify actually moving AC-130s into position. Schoomaker says, on the contrary, that he thought the AC-130 option feasible. The most likely explanation for the two generals' differing recollections is that both of them thought serious preparation for any such operations would require a long-term redeployment of Special Operations forces to the Middle East or South Asia. The AC-130s would need bases because the aircraft's unrefueled range was only a little over 2,000 miles.

Question: "What were the two things that Zinni worried about?"

OPTIONS:
- no
- yes

Answer: "That Bin Laden would locate himself in cities in the future and that Pakistani authorities would not get proper warning"

Response:
yes