Cooking food over a smoky fire is found everywhere in the world. It is often difficult to find wood for the fire. People who do not have wood must spend large amounts of money on cooking fuel. However, there is a much easier way to cook food using energy from the sun. Solar cookers, or ovens, have been used for centuries. A Swiss scientist made the first solar oven in 1767. Today, people are using solar cookers in many countries around the world. People use solar ovens to cook food and to heat drinking water to kill bacteria and other harmful organisms. There are three kinds of solar ovens. The first is a box cooker. It is designed with a special wall that shines or reflects sunlight into the box. Heat gets trapped under a piece of glass or plastic covering the top of the cooker. A box oven is effective for slow cooking of large amounts of food. The second kind of solar oven is a panel  cooker. It includes several flat walls, or panels, which directly reflect the sun's light onto the food. The food is inside a separate container of plastic or glass that traps heat energy. People can build panel cookers quickly and with very few supplies. They do not cost much. In Kenya, for example, panel cookers are being manufactured for just two dollars. The third kind of solar oven is a parabolic  cooker. It has rounded walls that aim sunlight directly into the bottom of the oven. Food cooks quickly in parabolic ovens. However, these cookers are hard to make. They must be re-aimed often to follow the sun. Parabolic cookers can also cause burns and eye injuries if they are not used correctly. You can make solar ovens from boxes or heavy paper. They will not catch fire. Paper burns at 232 degrees Celsius. A solar cooker never gets that hot. Solar ovens cook food at low temperatures over long periods of time. This permits people to leave food to cook while they do other things. To learn more about solar cooking, you can write to Solar Cookers International. The postal address is nineteen-nineteen Twenty-First Street,... How long is the first solar cookers invented? A) About 1767 years B) More than 300 years C) More than 250 years D) Less than 250 years
D

April 11, 2003 12:44 a. m. PST, Associated Press The respiratory  virus known as SARS has appeared to spread in the United States only to family members of health workers with close contact to a sick person. On Thursday, the head of the Centers for Disease Control and Prevention said there might be a case of severe acute respiratory syndrome  spreading through the workplace. Dr. Julie Gerberding said a suspected SARS virus patient who became ill after traveling to Asia might have infected a co-worker in Florida, which made her "very worried". So far, a dozen people--nine family members and three health workers--were infected after coming into close contact with the person with SARS. The rest of the 166 suspected American cases have something to do with people who were infected while traveling in Asia. In the Gainesville, Fla. area, a 47-year-old woman was believed to have been infected at work by a 60-year-old woman who was the nation's first suspected SARS case, said Tom Belcuore, director of the Alachua County health department. Since the World Health Organization announced a worldwide warning last month about SARS, the United States has started infection control in hospitals and among families of suspected cases. Florida officials said a school in Okaloosa County went through a cleaning after a 6-year-old boy suspected of having SARS appeared at school with slight symptoms. "Health officials are watching the boys' contacts at school to make sure no one else is infected," said Rob Hayes, health department spokesman, "The boy may have been infected from a family member," Hayes said, "We immediately became aware of it and had the child sent home. He's staying at home with his family until 10 days after symptoms disappear." The researchers guessed that the virus might have come from animals. However, the scientists have not ruled out the possibility that some other microbe might also help make SARS more serious or easier to catch. The best title for this text is   _  . A) A Worldwide Warning B) Suspected SARS Cases C) What Is SARS D) Possible Spread of SARS in the USA
D

Animal experts in Croatia say a bear has learned how to trick people to let him in by knocking at the door. They believe the 220- kilogram brown bear probably learned the trick while nudging   a door to get it to open. Experts have a guess that the nudging was mistaken by the owners for knocking and that the bear, pleased by the result, repeated the trick. The Loknar family from Gerovo in western Croatia said the bear had knocked at their door three times and they were now refusing to answer the door. ''We jumped out of the window as he came in through the door and went into the kitchen to take some food for the first time." Mum Nevenka Loknar told a reporter from a local newspaper. "I opened the door and saw him standing there and I didn't believe my eyes at first, then I ran for it as he walked in as if _ was the most normal- thing in the world." Bears are a common thing in the woods around here, but no one has ever heard of a bear that knocks at the door. Mum Nevenka Loknar said, "The bear is so intelligent. It's incredible. We've tried to put up lots of obstacles to stop him coming in, like a wire fence but he still gets through. I wouldn't be surprised if he knew how to use wire cutters." According to experts in Croatia, how did the bear learn the trick? A) By knocking at the door several times. B) By accident. C) By learning from the owner of a family. D) By imitation.

B