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Passage 44 For more than thirty years scientists have been searching for signs of life on other planets. Most of these searches have been done over the radio. The hope is that someone in outer space may be trying to get in touch with us. Scientists also have sent radio and television messages, as well as messages on spaceships traveling through space, on the chance that someone may be receptive to such messages. Scientists are using powerful radio telescopes to "listen" to signals from about 1,000 stars, all within 100 light years of the earth. In addition, they will scan the entire sky to listen for radio messages from more distant stars. Using a computer, they will be able to monitor more than eight million channels at a time. Scientists are looking for any signal that stands out from the background noise. Of the 200 billion stars in the Milky Way galaxy, scientists find that five percent of the stars are like our sun. Perhaps half of them have a planet like the earth. Such a planet would be a reasonable distance from the star for the temperatures to be right for the evolution of life. Believing that there are the inhabitable (that can be lived in) planets in our galaxy, most scientists agree that chances are that one or more of these planets support some life. However, many scientists wonder whether intelligent life exists on other planets. Some believe that thirty years of searching without any intelligent messages show that no one is out there. They say that the evolution of intelligence comparable to ours is unlikely. (44) Other scientists believe that our search hasn’t been long enough to rule out the possibility that intelligent life exists in our galaxy. Although our sun family is only about five billion years old, our galaxy is about 20 billion years old. In that time some scientists think it is likely that civilizations are much more advanced than ours. Perhaps these civilizations send us no signals; perhaps we have not recognized the signals they have sent us. If we hope to find intelligent life, these scientists believe that we have to keep looking. To look for signals from distant stars, scientists______.
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Passage 39 Many people have difficulty in studying mathematics. Sometimes their difficulty stems from the psychological idea that they are "not good at math". (39) It has been demonstrated that many times that it is often this idea that is causing their problems rather than any lack of skill in mathematics. The best way to deal with this problem is to tell yourself that math involves using the same numbers you have been using all your life and that you know them as well as anyone else. Then set your mind to learning how they are used in the particular part of mathematics you are studying. Many schools offer "math anxiety" courses which are designed to help people overcome their fear of math. Another problem many people encounter is that in mathematics, unlike some other subjects you may have studied, the material has a very important sequence or order. If you do not understand a section of mathematics text, it is no use going on to the next section. Many sections of math books are based on information presented earlier, so it is essential that you understand a section before going on to the next. Sometimes students in mathematics courses do not read the written material in the text but assume that the instructor will tell them what they need to know. This can cause them serious problems, since many instructors assume that students have read the text before coming to class. The written sections of mathematics textbooks contain much valuable information. The best way to solve this problem is______.
Passage 50 Young men often give flowers to young women when they are in love. This tradition may have come from Turkey. In the 1700s in Turkey, it was quite popular for people in love to send each other baskets full of strange things. The baskets were delivered secretly to the person who was receiving it. Usually, an old woman who sold flowers or fruit on the street left the basket beside the person’s door. These baskets included a variety of "gifts": flowers, stones, feathers, wax, and even charcoal. Each thing in the basket had a special meaning. By figuring out the secret message contained in each item, the person who received the basket began to understand little by little the true feelings of the person who sent it. (50) This idea of sending gifts of love with secret meanings quickly spread to Germany, France and England. However, as time passed, only sending flowers remained popular. An innocent bunch of flowers told young ladies about the feelings in the hearts of young men. Each different flower held a different meaning. For example, the flowers from an orange tree meant, "You are beautiful and pure." Pink carnations meant, "My love for you is strong and great." Yellow roses, on the other hand, meant, "I saw you with someone else. " Many flower dictionaries were made to help young people in love understand the meaning of the flowers they received. Not all of the dictionaries agreed, however, on the meaning of each flower, so a person had to be careful about the flowers they chose to send. By the 1880s, using flowers to send messages had fallen out of fashion, and the more direct way of sending love letters began. Today, flowers are still considered a lovely gift, but the meaning for each kind of flower has been lost. To which place did the idea of sending gifts of love spread
Passage 44 For more than thirty years scientists have been searching for signs of life on other planets. Most of these searches have been done over the radio. The hope is that someone in outer space may be trying to get in touch with us. Scientists also have sent radio and television messages, as well as messages on spaceships traveling through space, on the chance that someone may be receptive to such messages. Scientists are using powerful radio telescopes to "listen" to signals from about 1,000 stars, all within 100 light years of the earth. In addition, they will scan the entire sky to listen for radio messages from more distant stars. Using a computer, they will be able to monitor more than eight million channels at a time. Scientists are looking for any signal that stands out from the background noise. Of the 200 billion stars in the Milky Way galaxy, scientists find that five percent of the stars are like our sun. Perhaps half of them have a planet like the earth. Such a planet would be a reasonable distance from the star for the temperatures to be right for the evolution of life. Believing that there are the inhabitable (that can be lived in) planets in our galaxy, most scientists agree that chances are that one or more of these planets support some life. However, many scientists wonder whether intelligent life exists on other planets. Some believe that thirty years of searching without any intelligent messages show that no one is out there. They say that the evolution of intelligence comparable to ours is unlikely. (44) Other scientists believe that our search hasn’t been long enough to rule out the possibility that intelligent life exists in our galaxy. Although our sun family is only about five billion years old, our galaxy is about 20 billion years old. In that time some scientists think it is likely that civilizations are much more advanced than ours. Perhaps these civilizations send us no signals; perhaps we have not recognized the signals they have sent us. If we hope to find intelligent life, these scientists believe that we have to keep looking. Which of these statements is true based on the information in the passage
Passage 36 The market is a concept. If you are growing tomatoes in your backyard for sale you are producing for the market. You might sell some to your neighbor and some to the manager of the local supermarket. But in either case, you are producing for the market. Your efforts are being directed by the market. If people stop buying tomatoes, you will stop producing them. If you take care of a sick person to earn money, you are producing for the market. (36) If your father is a steelworker or a truck driver or a doctor or a grocer, he is producing goods or service for the market. When you spend your income, you are buying things from the market. You may spend money in stores, supermarkets, gas stations and restaurants. Still you are buying from the market. When the local grocer hires you to drive the delivery truck, he is buying your labor in the labor market. The market may seem to be something abstract. But for each person or businessman who is making and selling something, it’s very real. If nobody buys your tomatoes, it won’t be long before you get the message. The market is telling you something. It’s telling you that you are using energies and resources in doing something the market doesn’t want you to do. The underlined word "real" in the last paragraph may most probably mean______.
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