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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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【多选题】You are the network administrator for ExamSheet.net. Your network has 210 Windows 2000 Professional computers and eleven Windows 2000 Server computers. Users on the network save their work files in ho...
A.
Move the files from Sandra’s folder to the manager’s folder.
B.
Grant the manager NTFSFull Controlpermission to the files.
C.
Run theciphercommand to create a new file encryption key for the manager.
D.
Run theciphercommand to generate an EFS recovery agent key and certificate.
E.
Grant the manager NTFSList Folder Contentspermissions to the folder containing Sandra’s files.
【单选题】在SS9型电力机车风源系统管路原理图中
A.
没有设置无负荷启动电控阀
B.
采用的单塔式空气干燥器
C.
设置了一个总风缸
D.
有两个空气压缩机
【多选题】下列关于概率的说法,错误的是:____
A.
某事件发生的频率即概率
B.
某事件发生的频率即概率
C.
统计学上常将 P ≤ 0.05 的事件称为小概率事件
D.
在实际工作中,概率往往难以获得
E.
大小在 0 和 1 之间
F.
通常用 P 或 p 表示
【单选题】与小儿急性肾小球肾炎有关的主要病原体是
A.
柯萨奇病毒A
B.
肺炎链球茵
C.
乙型肝炎病毒
D.
金黄色葡萄球茵
E.
A组β溶血性链球茵
【单选题】关于儿童急性链球菌感染后肾小球肾炎的描述中,错误的是( )
A.
循环免疫复合物、原位免疫复合物以及补体系统均参与发病
B.
必须同时进行抗链球菌的治疗
C.
. 肾小球毛细血管袢和系膜区有 IgG 、 IgA 及 C3 等沉积
D.
肾小球滤过率急骤下降致水,钠潴留
E.
主要表现为非凹陷性水肿、血尿及蛋白尿等
【单选题】You have configured accessibility options for Tom. Everything works fine. You want to configure that when Tom wants to use CTRL, ALT or Shift key simultaneously, he should has the option to press one ...
A.
Turn on FilterKeys, this will allow accessibility options to be turned on at will.
B.
In accessibility options on the general tab, enable "turn off accessibility features after idle for  xx minutes".
C.
From the Keyboard tab of the accessibility option applet, check the StickyKeys checkbox, this  will save all accessibility options when you exit the control panel applet.
D.
In accessibility options on the general tab, disable "turn off accessibility features after idle for  xx minutes".
【单选题】与小儿急性肾小球肾炎有关的主要病原体是 ( )
A.
柯萨奇病毒
B.
肺炎链球菌
C.
乙型肝炎病毒
D.
金黄色葡萄球菌
E.
A 组 β 溶血性链球菌
【单选题】统计学常将P=0的事件称
A.
必然事件
B.
不可能事件
C.
随机事件
D.
小概率事件
E.
偶然事件
【简答题】职位评价是以( )为对象来进行的。 A 、员工 B 、员工能力 C 、工作职位 D 、其他
【单选题】下列关于概率的说法,错误的是:____
A.
某事件发生的频率即概率
B.
统计学上常将P ≤ 0.05或0.01的事件称为小概率事件
C.
在实际工作中,概率往往难以获得
D.
大小在0和1之间
E.
概率越大说明发生的可能性越大
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