"Iris scan , please," the bank's computer voice tells you . You step up and the computer reads your eye , comparing it to the stored file it has of your iris. The images had better match--otherwise you won't be able to get your money. Iris scanning and other technologies , such as fingerprint and voice scanning , have appeared in many science fiction movies in the past. Today , these advanced technologies are part of the real world. They are common at work, the bank, the airport, and your local prison. The iris scan, fingerprint scan, and voice scan are all examples of biometrics a fast developing area of automatic personal identification technology . Basically , biometrics uses various ways to verify a persons identity , based on the individual's unique characteristics ,including fingerprints , voices, irises, body heat patterns, facial images, handprints , signatures and so on. Biometrics identification systems have a number of advantages over password systems. The primary advantage is that an individual has to be physically present in order to be identified. Another important advantage is that there are no passwords to remember , forget, lose or steal. The voice scan is the simplest and most affordable form of biometrics . It only requires a computer, a microphone and the correct software. The software records a subject's voice and then compares it to a stored voice sample for identification purposes. For additional safety, fingerprint and handprint scans can also be employed . Fingerprint scans take the image of a fingerprint and compare it to a stored file of prints. Handprint scans identify the unique features of a hand. Iris scans currently give the highest level of accuracy among all the available biometrics systems. Another technology , full facial scans , is currently in use at border crossings and airports. Facial scanning equipment can actually track and identify moving faces within a crowd. The potential of biometrics is exciting and encouraging . With continued development , testing , and... Which is the most accurate form of biometrics? A) The voice scan B) The fingerprint scan C) The iris scan D) The facial scan
C
Ever since man began to use the telephone, there have been new problems arising from the carrying of messages. At first, each message was carried by a pair of overhead wires. As a result, telephone exchanges were soon surrounded by thousands of wires. The wires were then replaced by cables ,each containing many pairs of wires. Each cable is capable of carrying many messages. These cables, laid underground, replaced the overhead wires. The more _ telephone services have become, the more demand for these services has increased, particularly the demand for long-distance services. In China, for example, this growth is now over 30% every year. Long-distance telephone exchanges are usually in crowded cities, where is not easy to lay new labels for expanding services. The use of radio to send telephone message and to link all telephone exchanges makes it possible to get rid of overhead wires and some underground cables. Now man has invented the microwave system ( ). In a microwave system messages from various places can be brought together, and then they are sent out and received by radio. After that, the messages are split into their original form. Finally, they are sent to the places where they are going to be sent. The best title for the passage would be " _ ". A) The Telephone and Its Past B) From the Wire to the Microwave System C) The Needs for Better Telephones D) How to Use the Telephone
B
Q: Levi Strauss, who was born in 1830 and went to the USA at the age of 17, sat in the saloon and drank his beer slowly. He began to think. Business was not good. Nobody wanted to buy anything. He thought about the canvas and the pots and pans on the wagon. Then he remembered the hole in Hank's trousers. Suddenly, he had an idea -- "pants", he jumped up and shouted, "Everyone needs pants." He hurried to a tailor and gave him all his canvas. "I want you to make pants with this canvas," he said. "Can you do that?" "Yes, of course," said the tailor, "What name is it?" "Strauss, Levi Strauss." It was the beginning of jeans. Now more than a hundred years later, people wear jeans all over the world and everyone knows the name of Levi Strauss. In the 1860s, farmers, rail-road workers, cowboys and miners helped to develop the new land. Life was hard. They worked for long hours in all kinds of weather. They wore trousers made by Levi Strauss. They were the first people to wear jeans in America. Jeans first came to Europe with the American soldiers during World War II. Soon, workers in Europe were wearing them. Workers liked them: they were cheap, hardwearing and practical. They were not popular with young people generally until the late 1950s and early 1960s. It came suddenly. It started in America and it crossed the Atlantic quickly. It was a new kind of music, a new kind of dance. Rock' n Roll. The king of Rock' n Roll was Elvis Presley. Teenagers loved him. At home he wore a T shirt, an old leather jacket and blue jeans, so more and more teenagers began to wear jeans. They liked them tight. All the following statements are TRUE except _ . A) Jeans could first be seen in Europe during the Second World War B) Jeans were not popular with all Americans until the late 1950s and early 1960s C) Many people all over the world show interest in jeans at the present time D) Farmers, railroad workers, cowboys and miners were the first people to wear jeans in America
A: B
After a fortnight of extraordinary type, the much-feared computer virus that was supposed to strike the globe's hard drives last Friday simply fizzled. So many warnings were sounded that most computer owners either fed anti-virus programs into their systems or refused to turn the power on during the dreaded M-day. They dodged one disease, but more strains are on the way. The eponymous Friday-the-13th virus is due to strike this week, and the Maltese Amoeba may detonate on March 15. Who creates these things? A disproportionate number seems to originate in Bulgaria or Russia, where writing the smallest, most elegant virus programs has become a matter of quirky pride. Viruses are transmitted either by shared disks (as was Michelangelo) or over telephone lines. The virus program hides in a computer until, activated by a date, time, or some other trigger, it springs to life. The most common virus, Stoned, makes your screen announce: "Your computer is now stoned. Legalize marijuana. " (Regardless of your politics, you don't want this one around; it can damage your files inadvertently.) Solution: either keep your computer isolated--no trading disks, no on-line communication--or else install one of a dozen or so commercially available anti-virus programs that detect and delete the little time bombs. If they can come up with a virus that is hidden, will they next try to extort a business?--as in, pay me $1 million or my virus will destroy your system. In the meantime, money is being made by firms selling anti-virus programs. Egghead software stores logged a 3,000 percent jump in anti-virus sales. Was the threat overblown by the companies that make millions selling anti-virus software? Thanks to the media blitz, no one will ever know what might have happened--an unallied number of computer owners discovered and deleted Michelangelo before it was supposed to strike--on the artist's birthday. The author implies that in days to come the viruses might be used _ . A) to destroy data B) to commit crimes C) to commit mischief D) to create confusion
B