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【单选题】
Part Ⅱ Reading Comprehension (Skimming and Scanning) Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1. For questions 1-7, choose the best answer from the four choices marked A), B), C) and D). For questions 8-10, complete the sentences with the information given in the passage. Satellite Ⅳ Today, you see compact satellite dishes perched on rooftops all over the United States. Drive through rural areas beyond the reach of the cable companies and you'll find dishes on just about every house. The major satellite television companies are bringing in more customers every day with the lure of movies, sporting events and news from around the world. The Broadcast TV Problem Conceptually, satellite television is, a lot like broadcast television. It's a wireless system for delivering television programming directly to a viewer's house. Both broadcast television and satellite stations transmit programming via a radio signal. Broadcast stations use a powerful antenna to transmit radio waves to the surrounding area. Viewers can pick up the signal with a much smaller antenna. The main limitation of broadcast television is range. The radio signals used to broadcast television shoot out from the broadcast antenna in a straight line. In order to receive these signals, you have to be in the direct 'line of sight' of the antenna. One problem is that the Earth is curved, so it eventually breaks the signal's line of site. The other problem with broadcast television is that the signal is often distorted even in the viewing area. To get a perfectly clear signal like you find on cable, you have to be pretty close to the broadcast antenna without too many obstacles in the way. The Satellite TV Solution Satellite television solves the problems of range and distortion by transmitting broadcast signals from satellites orbiting the Earth. Since satellites are high in the sky, there are a lot more customers in the line of site. Satellite television systems transmit and receive radio signals using specialized antennas called satellite dishes. The television satellites are all in geosynchronous orbit, meaning that they stay in one place in the sky relative to the Earth. Each satellite is launched into space at about 7,000 mph (11,000kph), reaching approximately 22,200 miles (35,700km) above the Earth. At this speed and altitude, the satellite will revolve around the planet once every 24 hours—the same period of time it takes the Earth to make one full rotation. In other words, the satellite keeps pace with our moving planet exactly. This way, you only have to direct the dish at the satellite once, and from then on it picks up the signal without adjustment, at least when everything works right. The Overall System Early satellite TV viewers were explorers of sorts. They used their expensive dishes to discover unique programming that wasn't necessarily intended for mass audiences. The dish and receiving equipment gave viewers the tools to pick up foreign stations, live feeding between different broadcast stations, NASA activities and a lot of other stuff transmitted using satellites. Some satellite owners still seek out this sort of programming on their own, but today, most satellite TV customers get their programming through a direct broadcast satellite (DBS) provider, such as Direct TV or the Dish Network. The provider selects programs and broadcasts them to subscribers as a set package. Basically, the provider's goal is to bring dozens or even hundreds of channels to your television in a form. that approximates the competition, cable TV. Unlike earlier programming, the provider's broadcast is completely digital, whic
A.
a powerful antenna
B.
a much smaller antenna
C.
satellite dishes
D.
cable
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举一反三
【多选题】以下哪个概念不属于Web 3.0的范畴?
A.
门户网站
B.
万维网
C.
语义网
D.
物联网
E.
智能网
F.
大数据
【简答题】( )是指用信号或凭证,保证列车按照空间间隔制运行的技术方法。区间闭塞是指两分界点间,办理完闭塞手续的区间状态。
【单选题】每个网卡出厂时所分配的唯一地址标记又称为
A.
IP地址
B.
PIN号
C.
网卡名
D.
MAC地址
【多选题】扁平结构的特点主要表现在( )。
A.
有利于缩短上下级距离
B.
同级间相互沟通联络容易
C.
信息纵向流通快
D.
有利于选择和培养下属
E.
能够严密地监督下级
【单选题】以下哪个概念不属于Web 3.0的范畴?
A.
语义网
B.
智能网
C.
大数据
D.
万维网
【简答题】闭塞是指用信号或凭证,保证列车按照 运行的技术方法。A. 空间间隔制
【单选题】以下哪个概念不属于Web 3.0的范畴?
A.
门户网
B.
语义网
C.
物联网
D.
智能网
【单选题】在Excel中,以下 操作可以只删除所选数据区域的内容。
A.
“清除”|“清除批注”
B.
“清除”|“全部清除"
C.
”清除”|”清除内容”
D.
”清除”|”清除格式”
【判断题】闭塞是指用信号或凭证,保证列车按照空间间隔制运行的技术方法。区间闭塞是指两分界点间,办理完闭塞手续的区间状态。
A.
正确
B.
错误
【单选题】以下哪个概念不属于Web 3.0的范畴?
A.
物联网
B.
大数据
C.
万维网
D.
语义网
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