Read the following article and select the best answer. Article: When will a plant be considered a weed? Experts have a simple answer: when the undesirable qualities outweigh (,) the good qualities. Crops generally produce several hundred seeds from each plant. By comparison, each weed plant can produce tens or even hundreds of thousands of seeds. And some buried seeds can survive up to forty years or even longer. Eradicating weeds means that you have to remove all the seeds and roots so the weeds will die completely. But birds or the wind can reintroduce them to the land. A common way to deal with weeds is to control them enough so that the land can be used for planting. Experts suggest using more methods to deal with weeds. Chemical weed killers or natural treatments like corn gluten can suppress weed growth. Bill Curran is a professor of weed science. He says the most efficient method for suppressing weeds is dense planting. Dense planting of a crop can also act as a natural control. A dense and competitive crop that quickly shades the soil will help suppress many weeds. The weed seeds need light to grow, so cutting off sunlight will reduce weed growth. Other controls include turning over the soil, pulling the weeds or covering them with mulch made of wood, garden waste or other materials. But even mulch has its limits. Natural resource specialists point out that weeds can be transported in mulch. This is also true of soil, grain, hay and animals. Yet animals like sheep or goats eat weeds, so they can provide a biological control. Insects and other organisms can also act as biological controls. Preventing the spread of weeds is an important part of weed management. Farm vehicles should be kept out of areas with weeds. If that is not possible, then clean off the equipment and your shoes when leaving. Some people bum weeds or bury them deep. Experts say the economical way is to make organically rich compost . On the one hand, the process produces heat which can kill many weed seeds. On the other hand, the compost can be added to the soil to help plants grow. Question: What can we infer from the passage? - The weeds will surely die under mulch. - The buried weed seeds can't come out. - Farm vehicles should be used to kill weeds. - People can make good use of weeds properly.
People can make good use of weeds properly.

Read the following article and select the best answer. Article: 1826, a Frenchman named Niepce needed pictures for his business .But he was not a good artist.So he invented a very simple camera .He put it in a window of his house and took a picture of his garden .That was the first photo. The next important date in the history of photography was 1837. That year, Daguerre, another Frenchman, took a picture of his studio. He used a new kind of camera and a different processs. In his pictures, you could see everything very clearly, even the smallest details. This kind of photograph was called a daguerreotype. Soon, other people began to use Daguerre's process. Travellers brought back daguerreotypes from all around the world. People photographed famous buildings, cities and mountains. In about 1840, the process was improved. Now photographers could take pictures of people and moving things. The process was not simple. The photographers had to carry lots of film and processing equipment. But this did not stop the photographers, especially in the United States, where from the 1840s daguerreotype artists were popular in most cities. Mathew Brady was a well-known American photographer. He took many pictures of famous people. The pictures were unusual because they were very life-like and full of personality. Brady was also the first person to take pictures of war. His 1862 Civil War pictures showed dead soldiers and ruined cities. They made the war seem more real and more terrible In the 1880s, new inventions began to change photography. Photographers could buy film readymade in rolls. So they did not have to make the film immediately. They could bring it back to their studios and develop it later, meaning that they did not have to carry lots of equipment. And finally, the invention of the small handheld camera made photography less expensive. With the small camera, anyone could be a photographer. People began to use cameras just for fun. They took pictures of their families, friends and favourite places. They called these pictures "snapshots". Photographs became very popular in... Question: The first pictures of a war were taken by _ . - a French photographer in the 1840s - an American photographer in the 1860s - a German reporter in the 1880s - a French artist in the 1890s
an American photographer in the 1860s

Read the following article and select the best answer. Article: Old Computers Make for Unhappy Workers --- Survey LONDON (Reuters) ----- Dealing with the dissatisfaction of aging and unreliable office computers leads to workers' unhappiness and more sick leave, a survey showed on Wednesday. A survey carried out by caro4free.net of over 2,700 European office workers from the UK, France and Germany found that workplace dissatisfaction increased greatly with the age of the computer equipment. "We do know that job satisfaction is falling in Britain and most advanced nations," said Stephen White, a researcher from the Work Foundation. "The actual reasons for _ are the subject of very heated discussion. It's certainly one interesting theory that technology may be the cause of this in some way," White added. A quarter of these using outdated computers in Britain said they were "quite" or "very dissatisfied" with their everyday job compared to the percent of those who had enjoyed an advantage from up-to-date technology. The survey also said that among workers dealing with outdated equipment, there was a 35 percent greater probability they would take six or more days of sick leave per year compared with the average worker. In France, where more workers use old computers, the probability jumped to 55 percent. Results also showed that women in the three countries were more likely to be using outdated equipment. In the UK, where more workers have up-to-date computers than in the other countries surveyed, the number of women using old equipment doubled that of men. White pointed out that there were two sides to this problem, saying that continuously having to deal with new technology and equipment can also be a source of worry. "Old and faulty equipment is a major cause of office dissatisfaction. There is no question about it; but you also have to say that the frequent change of equipment is also, or could be, a main cause of dissatisfaction." Question: What is the subject of the news story? - Poor working conditions in offices - Research work of the Work Foundation - Influence of technology in the workplace. - Different attitudes to old computers.
Influence of technology in the workplace.