Can you imagine traveling to work in a one-man submarine? Scientists believe that someday one-man submarines will be as numerous as automobiles today. One says," One day soon, men will walk on the ocean floor as they do on the street. " Perhaps during your life time, people will travel, work and live under the sea. Ships carrying oil and articles of trade will move beneath the ocean. Passenger ships will be built to travel underwater, where storms cannot delay them or make people seasick. Special underwater ships will be designed for mining, fishing, and exploring unknown areas. For military use, there may be submarines that can fly and then dive underwater to approach the battle area without being seen. First, however, the human problems associated with living in the ocean will need to be studied in detail. Many of these problems are the same as the problems of living in outer space: pressure, lack of oxygen, and weightlessness. Already scientists have begun to study these problems. In 1963 and 1964 scientists and Navy divers lived and worked underwater for several days in two projects which were called Sealab I and Sealab II. The Sealab II experiment kept the scientists and divers 215 feet below the surface for thirty days, studying marine biology, temperature, pressure, currents, and ocean bottom geology. Many puzzling questions remain unanswered, however. Man's warm blood makes it difficult for him to live long in the sea without some kind of warmth. Can our blood be changed to fit new water surroundings? What will happen to our muscles if we live in the water very long? Will they become soft away from our usual land existence? Will bones become weak and our blood pressure change? Scientists are searching for answers. By studying plants and animals deep in the ocean, scientists may find a cure for some of our most serious human diseases. We may learn to use plants to increase our world food supply. Engineers may learn to use the power of the sea by building huge walls to catch the force of... According to the author,in future,passenger ships might be the ones that can _ A) be used for mining, fishing and exploring unknown areas B) carry oil and articles of trade C) travel underwater, not affected by storm D) fly and then dive underwater
C
*What prevents depression:tea,coffee or hot chocolate? Women who drink for or more cups of coffee a day are a fifth less likely to become depressed.Drinking two or three cups reduces the risk by 15 percent. This is the result of a study of 51,000 women over ten years, published in the Journal of the American Medicine Association. One theory is that caffeine reduces the effect of the chemical adenosine in the brain, which can make us feel sleepy by slowing down nerve cell activity. Some anti-depressants also work by blocking the adenosine receptors. Coffee was found to be far more influential on depression levels than hot chocolate or tea due to the high caffeine content. *How many eggs can we healthily eat: one a day or two a day? Neither-eat them freely. We've long been warned to stick to two or three eggs a week because of their high cholesterol content. But according to the Food Standards Agency, there is no recommended limit to how many eggs we can healthily eat, unless you have been told to cut down by your doctor. There is no evidence that eating eggs raises cholesterol levels, and researchers found that eggs contain less cholesterol than in the past because hens are no longer given bone meal, which was banned in the 1990s after the BSE cresis. Research by the British Egg Council found that a medium egg gives you around 100 mg of cholesterol, a third of the 300mg recommended daily limit. What is considered to fight depression best? A) Tea. B) Chocolate. C) Adenosine. D) Coffee.
D
Q: Keeping a busy social life among lots of friends may keep people thinner than spending hours doing some exercises, according to scientists. They say that socialising and meeting with friends help increase levels of brown fat in the body which burns calories to produce heat. Living in an exciting social environment was found to reduce fat in mice's belly by half over four weeks, even if they ate more. US researchers say that social excitement aids weight loss by turning white fat into brown. White fat stores calories and makes us fatter, while brown burns energy to produce heat. Turning white fat into brown is extremely difficult,normally requiring long- term stay in cold conditions or exciting part of the body's nervous system. However, scientists from Ohio State University now think that having a busy social life is an even more effective way of changing white fat into brown. The team came up with their theory by studying the effects of various living environments on mice. Those, who lived alongside a greater number of mice, had more space and toys to excite themselves and then lost far more weight over the course of the study than their "couch potato" fellows. Study author, Dr Matthew During, whose team's findings appear in the journal Cell Metabolism, said, "I'm still amazed at the degree of fat loss that occurs." Explaining how new technology had threatened face-to-face socialising, he added, "It's not just a sedentary( )lifestyle and high calorie foods, but an increasing lack of social activities." Co-author Dr Lei Cao said,"Loneliness is a potential factor for cancer and death; it's equal to cigarette smoking to a certain extent. Social activities are very vital.,, What's the main idea of the text? A) Brown fat is beneficial to people's health. B) Socialising is unnecessarily important in people's daily life. C) White fat can be changed into brown fat. D) Socialising contributes to people's losing weight.
A: D
Q: After students come home from a tiring day at school, they tend to worry a lot about their homework. Whether students are working on English or chemistry homework, they are simply working on the assignment in order to get it done, attempting to memorize the concepts for the time being and do not absorb any of the information afterward. Students are wasting their time on insignificant assignments rather than effectively using that time to achieve other accomplishments. According to www.dailymail.com, many parents are concerned that homework is being assigned rather than being used to integrate what teachers are covering in the classroom. In their eyes, if less homework is assigned, students would have much less stress and could focus more on their passions and hobbies. Homework gets in the way of participating in community service events as well as opportunities for getting a job or being a part of an extra-curricular activity. These responsibilities are important for teenagers to take on because they prepare the teenagers for the "real world." Without the proper exposure to work that is not school related, students will find themselves lost after they graduate. If homework were no longer given, students would have a lot more time to mature in other fields rather than being educated only on academics. In spite of the fact that teachers want students to do better on tests and absorb the material that they are teaching, homework is not accomplishing its purpose. Because school is becoming increasingly more competitive and challenging, homework is becoming a setback rather than extra practice. Its removal would benefit the well being of teenagers as well as encourage them to get out in the "real world" and discover themselves instead of staring at a pile of assignments. Students are wasting their time on insignificant homework because A) they are working on it carelessly and hurriedly B) they attempt to get only part of the information memorized C) they spend too much time doing it without understanding D) they fail to take in the information after finishing it
A: D