A

The US airline industry is facing a new threat to its profits — heavier passengers, a report has found. According to the US Centers for Disease Control and Prevention, the average US adult put on ten pounds (4.5kg) of weight during the 1990s. transporting the extra weight cost airlines an extra $275 million in fuel costs in 2000, the report says.

Earnings at airlines have already been under pressure due to the decreasing demand and a record increase in the price of crude oil. In the US, a number of airlines have gone bust while others are struggling to survive in an ever more competitive marketplace. While it is relatively easy to check the weight of a traveler’s luggage and charge those that burst limits, it is much harder to regulate a person’s waistline. Some firms have toyed with the idea of (jokingly suggested) charging overweight travelers for two seats, but it is not a practice that has taken off industry-wide.

Last year, the American Federal Aviation Administration increased the average passenger weight they use to calculate aircraft loads by ten pounds. Since then, crude oil prices have hit record levels, with many firms responding by raising the fuel charge they add to ticket prices.

The rising level of obesity in the US and in Europe has prompted government health campaigns and harsh criticism of a number of food firms. Restaurant chain McDonald’s has taken the main force of the attack, and has in recent months reworked its menu to include healthier option, which has helped lift profits.

As with fast food restaurants, timely adjustment may be the best solution presently for American airlines. The prediction by experts, however, is that humans are set to become bigger.

41. This passage is most probably taken from______.

A. a government reportB. a yearly economy review

C. an airline guidebookD. a newspaper

42. The underlined phrase “gone bust” (paragraph 2) is closest in meaning to_________ .

A. become strongerB. got banned___C. failed financially___D. expanded further

43. What measures did many American airlines take in response to the record increase in the price of crude oil last year?

A. They increased the average passenger weight when calculating aircraft loads.

B. They brought up their ticket prices.

C. They charged obsess travelers for two seats.

D. They overcharged travelers’ luggage.

44. What does the last paragraph of the passage imply?

A. Airline profits in America will be under even greater pressure.

B. The population of obsess people will increase rapidly.

C. American airlines will charge more for fuels.

D. Fast food restaurants will be forced to change their menus.

A device that stops drivers from falling asleep at the wheel is about to undergo testing at Department of Transport laboratories and could go on sale within 12 months.

The system, called Driver Alert, aims to reduce deadly road accidents by 20% - 40% that are caused by tiredness.

Driver Alert is based on a computerized wristband. The device, worn by drivers, gives out a sound about every four minutes during a car journey. After each sound the driver must respond by squeezing the steering wheel (方向盘). A sensor in the wristband detects this pressing action and measures the time between the sound and the driver’s response.

Tiredness is directly related to a driver’s response time. Usually a watchful driver would take about 400 milliseconds to respond, but once that falls to more than 500 milliseconds, it suggests that the driver is getting sleepy.

In such cases the device gives out more regular and louder sounds, showing that the driver should ou0en a window or stop for a rest. If the driver’s continues to slow down, the sounds become more frequent until a nonstop alarm warns that the driver must stop as soon as possible.

The device has been delivered to the department’s laboratories for testing. If these tests, scheduled for six months’ time, are successful, the makers will bring the product to market within about a year.

45. According to the text, Driver Alert____________.

A. aims to reduce tiredness-related accidentsB. has gone through testing at laboratories

C. aims to prevent drivers from sleepingD. has been on sale for 12 months

46. How should a driver respond to the sounds from Driver Alert?

A. By sounding a warning.B. By touching the wristband.

C. By checking the driving time.D. By pressing the steering wheel.

47. We can learn from the text that the driver needs to stop for a break when his response time is __________.

A. about 400 millisecondsB. below 500 milliseconds

C. over 500 millisecondsD. about 4 minutes

48. When the driver gets sleepy while driving, Driver Alert ______.

A. moves more regularlyB. stops working properly

C. opens the window for the driverD. sounds more frequently and loudly

Desert plants fall into sorts according to the way the deal with the problem of surviving drought. There are the drought-avoiders-those which persist (存留) only as seeds, ready to spring up when it rains, to flower quickly and produce another crop of seeds, and to die again. There are also the drought-resisters-those which have evolved various methods for strong water, locating underground water, or reducing their need for water by such devices as shedding their leaves. The drought-resisters are perennials (多年生植物), they manage to live from one rainy season to another, slowly growing bigger and bigger. Of these, the succulent (肉质植物) is a small but interesting fraction (小部分). They may store water in their leaves, in their stems, or in underground containers.

In the American deserts the best-known succulents are the cacti (仙人掌). They come in a wide range of sizes, from 50-foot tall giant saguaros (树形仙人掌) to tiny round cacti about the size of a thumb-nail. They take thick, cylindrical (圆柱体) or even spherical forms, thereby exposing a minimum of evaporating surface to the air and light. They are leafless, except in youth, and then the leaves are small. Typically their surfaces are spiny, discouraging thirst animals, and channeled like an accordion (手风琴), so the fleshy stem may expand quickly when the plant drinks and contracts slowly as it uses up the water. The root system is widespread and shallow, with good reason – only about 3 percent of the rain that falls on the desert penetrates to any significant depth into soil.

49. The passage classifies the desert plants according to ______.

A. the ways they take to deal with the typical climate condition in desert

B. their shapeC. how they use waterD. when they produce their seeds

50. According to the passage, some desert plants drop their leaves ______.

A. because the temperature is too highB. so that the plants can evaporate less water

C. because they are drought-resistersD. so that the plants can store more water

51. What interests the author most when he or she mentions succulents is that _______.

A. they take thick cylindrical or even spherical shape

B. they are best-known in America

C. they have many ways of containing water

D. some of them can be very tiny

52. The passage gives us an impression that ______.