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A．A sectary.B．A tour guide.C．An attorney.D．A travel agent.
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Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
The gravitational pull of the earth and moon is important to us as we attempt to conquer more and more of outer space. Here's why.
As a rocket leaves the earth, the pull of the earth on it becomes less and less as the rocket roars out into space. If you imagine a line between the earth and the moon, there's a point somewhere along that line, nearer to the moon than to the earth, at which the gravitational pull of both the earth and the moon on an object is just about equal. An object placed on the moon side of that point would be drawn to the moon. An object placed on the earth side of that point would be drawn to the earth. Therefore, a rocket need be sent only to this "point of no return" in order to get it to the moon. The moon's gravity will pull it the rest of the way.
The return trip of the rocket to the earth is, in some ways, less of a problem. The earth's gravitational field reaches far closer to the moon than does the moon's to earth. Thus, it will be necessary to fire an earthbound rocket only a few thousand miles away from the moon to reach a point where the rocket will drift to earth under the earth's gravitational pull.
The problem of rocket travel is not so much concerned with getting the rocket into space as it is with guiding the rocket after it leaves the earth's surface. Remember that the moon is constantly circling the earth. A rocket fired at the moon and continuing in the direction in which it was fired would miss the moon by a wide: margin and. perhaps continue to drift out into space until "captured" in another planet's gravitational field. To reach the moon, a rocket must be tired toward the point where the moon will be when the rocket has traveled the: required distance. This requires precise calculations of the speed and direction of the rocket and of the speed and direction of the moon.
For a rocket to arrive at a point where the moon's gravity will pull it the rest of the way, it must reach a speed called the velocity of escape. This speed is about 25, 000 m/les (about 40,200 kilometers) per hour. At a speed less than this, a rocket will merely circle the earth in an orbit and eventually fall back to the earth.
This short passage is mainly about ______.
听力原文： We all scream for water when thirsty. But do you know that in very hot dry weather, plants also make faint sounds as if they am crying out for help？ You see, in a plant' s stem, there are hundreds of water pipes that bring water and minerals from the soil all the way up to the leaves. As the ground turns dry, it becomes harder and harder for the plants to do this. In severe droughts, plants have to fight to pull out any water available. Scientist Robert Winter has found out that when it is really bad, their water pipes snap from the tension like rubber bands. When that happens, the whole plant vibrates a little. The snapping pipes make noises ten thousand times more quiet than a whisper.
Robert knows that healthy well-watered plants are quiet. He also knows that many insects prefer a attacking dry plants rather than healthy plants. How do the insects know which are healthy plants and which are not？ Robert thinks that the insects may listen for the plants that cry, and then they may buzz in m kill. To test his theory, Robert is using a device that can imitate plant cries. He attaches it to a quiet healthy plant so that the plant sounds thirsty. Then he watches the insects to see ff they attack more often than usual. If he is fight, scientists could use the insects' ability against them. They could build traps that imitate crying plants, so that when the insects buzz in to eat, they won' t buzz out.
(30)
听力原文：M: It has just struck six p.m..
W: Hmm. Well, the road's not busy, so we should be home in about one hour. But we'll take a break of about twenty minutes for tea.
Q: What time will they get home？
(13)
Newton was very creative in thinking and solving problems when he was a little boy.
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