阅读理解 Navigation computers, now sold by most car makers, cost $ 2000 and up. No surprise, then, that they are most often found in luxury cars, like Lexus, BMW and Audi. But it is a developing technology-meaning prices should eventually drop-and the market does seem to be growing. Even at current prices, a navigation computer is impressive, It can guide you from point to point in most major cities with precise turn by-turn directions spoken by a clear human sounding voice, and written on a screen in front of the driver. The computer works with an antenna that takes signals from no fewer than three of the 24 Global Positioning System (GPS) satellites. By measuring the time required for a signal to travel between the satellites and the antenna, the car''s location can be pinned down within 100 meters. The satellite signals, along with inputs on speed from a wheel speed sensor and direction from a meter, determine the car''s position even as it moves. This information is combined with a map database. Streets, land marks and points of interest are included. Most systems are basically identical. The differences come in hardware-the way the computer accepts the driver''s request for directions and the way it presents the driving instructions. On most systems, a driver enters a desired address, motorway junction or point of interest via a touch screen or disc. But the Lexus screen goes a step further: you can point to any spot on the map screen and get directions to it. BMW''s system offers set of cross hairs that can be moved across the map (you have several Choices of map scale) to pick a point you''d like to get to. Audi''s screen can be switched to TV reception. Even the voices that recite the directions can differ, with better systems like BMW''s and Lexus''s having a wider vocabulary. The instructions are available in French, German, Spanish, Dutch arid, Italian, as well as English. The driver can also choose parameters for determining the route: fastest, shortest or no freeways, for example.

单选题 We learn from the passage that navigation computers ______.

A、 will greatly promote sales of automobiles
B、 may help solve potential traffic problems
C、 are likely to be accepted by more drivers
D、 will soon be viewed as a symbol of luxury

【正确答案】 C

【答案解析】推理题。此题的关键是要注意第一段的转折连词“but”。既然这种电脑是一种发展中的技术，价格应当会降下来，市场的潜力很大，所以可以合理地推理出“它有可能被更多的驾驶者接受”。

单选题 With a navigation computer, a driver will easily find the best route to his destination ______.

A、 by inputting the exact address
B、 by indicating the location of his car
C、 by checking his computer database
D、 by giving vocal orders to the computer

【正确答案】 A

【答案解析】细节理解题。相关内容在第五段第三句“在许多系统里，司机输入想要去的地址，高速公路交叉点和风景点…”。B,C两项未被提到。D项中的“vocal orders”与pointing to any spot on the map screen相反。

单选题 Despite their varied designs, navigation computers used in cars ______.

A、 are more or less the same price
B、 provide directions in much the same way
C、 work on more or less the same principles
D、 receive instructions from the same satellites

【正确答案】 C

【答案解析】细节理解题。文章第五段第一句中“basically identical”与选项C表述中的“same principles”相吻合，故为正确答案。

单选题 The navigation computer functions ______.

A、 by means of a direction finder and a speed detector
B、 basically on satellite signals and a map database
C、 mainly through the reception of turn-by-turn directions
D、 by using a screen to display satellite signals

【正确答案】 B

【答案解析】推理题。此题考察对第四段的理解。“The satellite signals...determine the car''s position”及“This in formation is combined with a map data base”与选项B的表述相吻合，因此为正确答案。

单选题 The navigation systems in cars like Lexus, BMW and Audi are mentioned to show ______.

A、 the immaturity of the new technology
B、 the superiority of the global positioning system
C、 the cause of price fluctuations in car equipment
D、 the different ways of providing guidance to the driver

【正确答案】 D

【答案解析】典型的例证型细节题。本文第五段第二句讲的是系统的不同之处在于硬件，比如电脑接受驾驶者要求的方式不同，以及提供指令的方式不同，接着文章用三款豪华轿车为例来说明。因此D为正确答案。