disaster in 2094?

　A. The whole world becomes extremely cold.

　B. All the coastal cities in Africa are destroyed.

　C. The whole mankind becomes extinct.

　D. The visit of the comet results in wars.

2. Why does the author mention dinosaurs at the end of the passage?

　A. Because they could only live in the warm climate.

　B. Because they once dominated the earth.

　C. Because their extinction indicates future disasters.

　D. Because dinosaurs and humans never live in the same age.

3. In writing the passage, the author intends to ________.

　A. give an accurate description of the possible disaster in the future

　B. prove that humans will sooner or later be destroyed

　C. tell the historical development of the earth

　D. warn of a possible disaster in the future

4. It can be concluded that the passage is most probably part of a(n)________.

　A. horror story B. news report

　C. research paper D. article of popular science

　　Satellites are an important part of our ordinary lives. For example, the information for weather forecasts is sent by satellite. Some satellites have cameras which take photographs of the Earth to show how clouds are moving. Satellites are also used to connect our international phone calls.

　　Computer connections of the World Wide Web and Internet also use satellites. Many of our TV programmes come to us through satellites. Airplane pilots also sometimes use a satellite to help them find their exact location.

We use satellites to send television pictures from one part of the world to another. They are usually 35，880 kilometres above the equator. Sometimes we can see a satellite in the sky and it seems to stay in the same place. This is because it is moving around the world at 11，000 kilometres an hour-exactly the same speed that the earth rotates. A satellite must orbit the Earth with its antennae (天线) facing the earth. Sometimes, it moves away from its orbit. So there are little rockets on it which are used to put the satellite back in the right position. This usually happens about every five or six days.