题目内容
Navigation computers, now sold by most car-makers, cost $2,000 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(天线) 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 noted 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, landmarks 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 a set of cross hairs(瞄准器上的十字纹) 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 and Italian, as well as English. The driver can also choose parameters for determining the route: fastest, shortest or no freeways (高速公路), for example.
46. 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
47. 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
48. 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
49. 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
50. 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 change in car equipment
D. the different ways of providing guidance to the driver
46-50: CACAD
解析:
46.推理判断题,从文章中第一段可得知。
47.细节理解题。 从第二段句子可以正确理解。
48.推理判断题,点比较分散要通读全文。
49.细节理解题,分散阅读可以获得信息。
50.推理判断题。从最后一段可以推断出。
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Why don’t birds get lost on their long migratory (迁居的) flights? Scientists have puzzled over this question for many years. Now they’re beginning to fill in the blanks.
Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly mainly by night? Tests with artificial stars have proved conclusively that certain night-flying birds are able to follow the stars in their long-distance flights.
One such bird, a warbler(鸣禽) , had spent its lifetime in a cage and had never flown under a natural sky. Yet it showed an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky at migration time. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the direction of the make-be-live stars caused a change in the direction of his flight. Scientists think that warblers, when flying in daylight, use the sun for guidance. But the stars are apparently their main means of navigation (导航). What do they do when the stars are hidden by clouds? Apparently, they find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the warblers circle helplessly, unable to get their direction.
【小题1】The reasons why birds don’t get lost on migratory flights__________.
A.have been known to scientists for many years |
B.are known by everyone |
C.have only recently been discovered |
D.will probably remain a mystery |
A.from North America to South America |
B.using what is apparently an inborn navigational ability |
C.only once during their lifetime |
D.when they are freed from their cages |
A.an artificial star | B.some landmarks |
C.their inborn ability | D.A and B |
A.discover workable answers to universal questions by studying particular cases(特别案例) |
B.jump to conclusions |
C.find a law and then investigate(调查) |
D.are disappointed by the habits of animals |
American Watersports Tuesday-Saturday
Located on the beach of the Sea Gardens Beach Resort, there are fun things to
rent for the whole family. They offer rentals for kayaks, jet skis, and even parasail!
Enjoy the water up-close or from a bird’s eye view! No matter what activity you’re
enjoying, be sure to protect yourself and your family from the sun’s powerful rays and apply plenty of sun block!
15th Street Boat Company Monday-Saturday
15th Street Boat Company offers rental boats of all kinds. They’re sure to have what you are looking for, whether it’s a small boat for a quick and simple outing or an extravagant boat with comfortable seats with a stereo and high tech navigation. You can rent a boat for half a day or a couple of days, or even weeks at a time. If you want it, they’ve got it. It’s fun for everyone!
Coconut’s Watersports 9am-5pm Monday-Sunday
Coconut’s Watersports is open 7 days a week and offers tons of water fun for the whole family. Jet Ski activities last 30 minutes or 1 hour and can make stops along the way. You must be at least 14 years of age to ride alone and can be as young as 3 to ride along with an adult. Everybody is required to wear a life jacket and a license is required to operate the Jet Ski. Bathing suits and shorts are recommended.
Jet Ski Tours of Miami 10am-7pm Thursday-Sunday
Jet Ski Tours of Miami includes onsite parking, indoor restrooms, lockers, and life jackets for participants. You may choose a one or two tour and each Jet Ski can hold up to 3 people. You must be at least 18 years old in order to ride. As long as you are accompanied by an adult, there is no age limitation for any passenger. There is a restaurant nearby to eat at. The tour visits 6 different islands and passes by Bayside and Hard Rock. You may even catch sight of dolphins, turtles or a crab resting in these splendid Florida waters.
1.You should especially protect yourself from sun burnt while visiting______.
A.Jet Ski Tours of Miami |
B.Coconut’s Watersports |
C.15th Street Boat Company |
D.American Watersports |
2.Which of the following can help you enjoy sailing a boat?
A.Go to the Sea Gardens Beach Resort. |
B.Visit 15th Street Boat Company. |
C.Choose Jet Ski Tours of Miami. |
D.Visit Coconut’s Watersports. |
3.What’s a must to ride alone in the Jet Ski activities?
A.One must be at least 14 years old. |
B.One must wear bathing suits and shorts. |
C.One must apply plenty of sun block. |
D.One must be accompanied by parents. |
4.What will you do to satisfy your son’s curiosity about sea animals?
A.You would like to rent a boat to ride with him. |
B.You need a boat with comfortable seats with a stereo. |
C.You’d like to choose American Watersports. |
D.You prefer the tour to Bayside and Hard Rock. |