Television broadcasts are 71 to an area that is within the 72 of the sending station or its relay(中转站).73 television relays are often placed on hills and mountains so that they can 74a wider region, they still can not cover more [and than one from the hilltop 75a clear day.However, the rays also go out into the atmosphere, 76there is a relay station on a satellite that 77 around the earth, it can send the pictures to any point on the earth from which the satellite is 78 Three satellites 79 . turning around over the equator(赤道)send any television program to any part of the earth.80 makes it possible for world 81of newspapers to give-the news in all countries at the same time.82 it may be possible for a subscriber (订户)to a televised news-paper to 83 a button and see a newspaper page 84 his television screen. He could also decide when he wants the page 85 , 86 , by dialing different such as87 on a telephone dial, he could choose the language or the edition of the paper hewants to read. It seems strange to think that, even today, methods of the 88 are not entire ly useless. For example, sometimes89agencies which use radio and Telstar also use pigeons to 90 messages between offices in large cities because the pigeons are not bothered by traffic problems.根据以上内容,回答题。 材料题请点击右侧查看材料问题 查看材料