Ques:As in the field of space travel, new technologies continue to appear in undersea exploration. They share a number of similarities with each other -- as well as some important differences. Manned submersibles  , like spaceships, must maintain living conditions in an unnatural environment. While a spaceship must simply be sealed against the vacuum space, a submersible must be able to bear extreme pressure if it is not to break up in deep water. In exploring space, unmanned vehicles were employed before astronauts. In undersea exploration, on the other hand, men paved the way, and only recently have unmanned remote-operated vehicles (ROVs) been put to use. One reason for this is that communicating with vehicles in orbit is much easier than talking to those underwater. A vacuum is an ideal medium for radio communications, but underwater communications are limited to much slower sound waves. Thus, most undersea vehicles -- particularly ROVs -- operate at the end of long ropes.  For a similar reason, knowing where you are undersea is much more difficult than in space. A spaceship's position can be located by following its radio signal, or by using telescopes and radar. For an undersea vehicle, however, a special network of sonar  devices must be laid out in advance on the ocean floor in the area of a dive to locate the vehicle's position. Though undersea exploration is more challenging than outer space in a number of respects, it has a distinct advantage: going to the ocean depths doesn't require the power necessary to escape Earth's gravity. Thus, it remains far less expensive. The sonar devices must be placed   _  . A) from time to time B) after the undersea vehicles dive C) before the undersea vehicles dive D) when the undersea vehicles are diving

Ans:C
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Ques:When his wife died, one baby was two. They had six other children, three boys and three girls, ranging in age from 4 to 16. A few days after he became a  _ the man's parents and his past wife's parents came to visit the family. ''We've been talking' they said,'' about how to take care of all these children and work to make a living. So, we've arranged for each child to be placed with a different uncle or aunt. We're making sure that here in the neighborhood, so you can see them at any time'' ''you have no idea how much I appreciate your thoughtfulness.' The man said .''But I want you to know,'' he smiled and continued, '' if the children affect my work or if we should need any help, we'll let you know.''   Over the next few weeks, the man worked with his children, assigning them small work and giving them responsibilities. But then another misfortune happened. The man got a disease-- arthritis. His hands swelled, and he was unable to catch the handles of his farm tools. The children did their work well, but the man could see that he would not be able to continue the work on his farm, He sold his farming equipment, moved the family to a small town, and opened a small business, The family was welcomed into the new neighborhood. The man's business flourished soon. He got pleasure from seeing people and serving them. Word of his pleasant personality and good customer service began to spread in the town. People came from far and wide to do business with him, and the children helped both at home and at work, Their father's pleasure in his work brought courage to them and the father got pleasure from their success.  The children grew up and got married. Five of the seven went to college and then they were married. Each one paid his or her own way. The children's success in school was a source of pride to the father, as he had stopped at the sixth grade .Then came grandchildren .No one enjoyed grandchildren more than this man. As they became older, he invited them to his workplace and his small home .They brought... The main idea of the passage is   _  . A) The father's life work: raising his family B) why the father wanted to raise his family C) how the children grew up after their mother died D) the father's effects on his children

Ans:A
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Ques:What a Scientist Is Like If you were asked to imagine a scientist, what image  would come to your mind? The common idea that most kids from kindergarten through college have of a scientist is a man wearing a white lab coat with messy hair, big glasses, and several glass cups of mysterious color1ful liquids giving off clouds of smoke. As for adults, the majority view scientists as strange people who spend 100 hours a week slaving away in a lonely laboratory. However, the reality is quite different. Recently I've had a chance to take part in a scientific experience far from my laboratory and into Costa Rica. It supports a huge amount of wildlife due to its geographical placement between North and South America. It is home to more than 500,000 species  ,which represents nearly 4% of the total species worldwide! First we worked alongside conservationists to preserve wildlife at a leatherback turtle ( )rescue center. We helped the volunteers preserve turtle populations by removing rubbish from the shoreline to create a safe environment for turtle eggs to come out. After that we stayed at Mount Arenal where we studied seismic activity relating to earthquakes. During our stay at Arenal, we rode over the mountainous areas and took a long walk through the rainforest. After reaching the top, we went down and through waterfalls to the beautiful valley below! On the last day we got a hands-on introduction to rocket science where we learned about new rocket technology that will be used on the international space station. During my Costa Rica experience, I know that being a scientist doesn't mean working in a lab all day and night. A scientist is one who loves learning and getting a better understanding of the world from helping preserve wild-life, learning about earthquakes or inventing rockets. I think that schools should really stress that science is so much more than wearing a lab coat and mixing chemicals. Kids need to be aware of the excitement and adventures science can bring! What does the author learn about science from his experience? A) Science is full of boring experiments. B) Science is more than working in a lab. C) Science is related to mysterious liquids. D) Science is about wildlife and earthquakes.

Ans:
B
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