I've lived my whole life in Spanish Harlem with my mom, and I never have a father. I have friends who ended up in jail or pregnancy. But Mr.Clark wouldn't let that happen. Mr. Clark worked long hours, making sure I did my work. My grades rose. In fact ,our whole fifth-grade class's scores rose in math and reading. In sixth grade, I entered the gifted program, and Mr. Clark was the teacher. I felt so lucky to have him for a second year ! None of us were surprised when Mr.Clark was selected as Disney's 2004 Teacher of the Year. When he learned he'd won, he said he would draw three names out of a hat; those students would go with him toprefix = st1 /Los Angelesto get the award. But when it came time to draw names, Mr. Clark said, " You're all going." He got donations to fly all 37of us out to Disneyland inCaliforniaand put us at the Hilton. We were there for three days. People were amazed, but Mr. Clark really cared about us. There's no way I can imagine most teachers doing that. No way. But he saw something in us that nobody else saw. On graduation day ,there were a lot of tears. We didn't want his class to end. In 2005,he moved toAtlanta, but we always kept in touch. He started giving speeches about education and wrote a best-selling book based on his classroom rules. In 2007,Mr.Clark took some of us on a trip toSouth Africato deliver school supplies and visit orphanages. It was the most amazing experience of my life. It's now my dream to start a group of women's clubs one day, helping people from all backgrounds. I'm about to become a senior atHarlemRenaissanceHigh School. My grades are beautiful now, and I'm hoping to go to law school eventually. This fall, Mr.Clark will be opening the Ron Clark Academy inAtlanta, a school for kids who have potential but aren't reaching it, kids who are like I was -- until Mr.Clark came along. Which of the following is the best title for the passage? A) How I Improved My Grades B) Trips with My Teacher C) Lucky to Have Him D) My High School Years
C
He has climbed a high mountain, raced the 24-hour motorcycle track in France and even, walked from Tokyo to Kyoto, a distance of 500 km. Now Evolta, Panasonic's 7-inch Humanoid Robot is getting ready for his biggest challenge -- the Ironman Triathlon Championship in Hawaii. To compete in this exhausting contest, the green & white robot which is small enough to fit on a human palm, will have to swim 2.4 miles in the rough ocean, bike 112 miles across the hot Hawaiian desert and, run a full marathon distance of 26.2 miles in the painfully hot weather. Given that he is so tiny and powered by rechargeable batteries of Panasonic, he will be allowed some freedom in the way he competes. For one, he will be starting the race on October 23rd, 2011, three weeks following the real event and, while human competitors have at most 17 hours to complete the triathlon, Evolta will be given 7 days, during which his only "breaks" will be to recharge his batteries. The biggest difference however, will be that unlike a single human body doing all three races, there will be three different "Evolta" robot bodies competing -- each built for the specific race. Evolta the swimmer will be equipped with special arms to swim forward. Evolta the biker, will be on a little two-wheeler with training wheels, while Evolta the runner, will be fixed on what looks like a wheel. In spite of all these advantages, the robot's creator Tomotaka Takahashi believes that the race will be a huge challenge -- not only will Evolta have to battle the wind and sun, but also, small road obstacles that humans just step over. The water will be even worse thanks to the strong waves, tides and ocean winds. But if he does complete it, Evolta will add another feather in his cap and just prove the already well-known fact that Panasonic's rechargeable Evolta batteries are indeed the "world's longest-lasting batteries"! The text is mainly about a robot _ . A) using the energy-efficient batteries B) accomplishing a challenging triathlon C) winning human athletes for the first time D) competing in the Ironman Triathlon Championship
D
*Question*
Knots are the kind of stuff that even myths are made of.In the Greek legend of the Gordian knot, for example, Alexander the Great used his sword to slice through a knot that had failed all previous attempts to unite it. Knots, enjoy a long history of tales and fanciful names such as "Englishman's tie, " "and "cat's paw. " Knots became the subject of serious scientific investigation when in the 1860s the English physicist William Thomson (known today as Lord Kelvin) proposed that atoms were in fact knotted tubes of ether . In order to be able to develop the equivalent of a periodic table of the elements, Thomson had to be able to classify knots -- find out which different knots were possible. This sparked a great interest in the mathematical theory of knots. A mathematical knot looks very much like a familiar knot in a string, only with the string's ends joined. In Thomson's theory, knots could, in principle at least, model atoms of increasing complexity, such as the hydrogen, carbon, and oxygen atoms, respectively. For knots to be truly useful in a mathematical theory, however, mathematicians searched for some precise way of proving that what appeared to be different knots were really different -- the couldn't be transformed one into the other by some simple manipulation . Towards the end of the nineteenth century, the Scottish mathematician Peter Guthrie Tait and the University of Nebraska professor Charles Newton Little published complete tables of knots with up to ten crossings. Unfortunately, by the time that this heroic effort was completed, Kelvin's theory had already been totally discarded as a model for atomic structure. Nevertheless, even without any other application in sight, the mathematical interest in knot theory continued at _ point for its own sake. In fact, mathematical became even more fascinated by knots. The only difference was that, as the British mathematician Sir Michael Atiyah has put it, "the study of knots became a special branch of pure mathematics. " Two major breakthroughs in knot... According to the passage, _ shows the most updated study about knots. A) t 2-t+1 B) t 2-3t+1 C) Alexander polynomial D) Jones polynomial
**Answer**
D