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Volts from the Sky 1．Lightning has caused awe and wonder since old times. Although Benjamin Franklin demonstrated lightning as an enormous electrical discharge more than 200 years ago, many puzzles still surround this powerful phenomenon. 2．Lightning is generated when electrical charges separate in rain clouds, though processes are still not fully understood. Typically, positive charges build at the cloud top, while the bottom becomes negatively charged. In most instances of cloud-to-ground lightning, the negatively charged lower portion of the cloud repels negatively charged particles on the ground’s surfaces, making it become positively charged, The positive charge on the ground gathers at elevated points. 3．A flow of electrons begins between the cloud and earth. When the voltage charge becomes large enough, it breaks through the insulating barrier of air, and electrons zigzag earthward. We see the discharge as lightning. 4．Lightning can occur within a cloud, between clouds, or between clouds and the ground. The first variety, intra-cloud lightning, is the most frequent but is often hidden from our view. Cloud-to -ground lightning, making up about 20 percent of lightning discharges, is what we usually see lightning comes in several forms, including sheet, ribbon, and ball, Intra-cloud lightning can illuminate a cloud so it looks like a White sheet, hence its name. When cloud-to-ground lightning occurs during strong winds, they can shift the lightning channel sideways, so it looks like a ribbon. The average lightning strike is more than 3 miles long and can travel at a tenth of the speed of light. Ball lightning, the rarest and most mysterious form, derives its name from the small luminous ball that appears near the impact point, moves horizontally, and lasts for several seconds. 5．Thunder is generated by the tremendous heat released in a lightning discharge second. This sudden heating acts as an explosion, generating shock waves we hear as thunder. 6．About 2,000 thunderstorms are occurring in the world at any time, generating about 100 lightning strikes every second, or 8 million daily. Within the United States, lightning strikes are estimated at 20 million a year, or about 22,000 per day. You have a 1-in-600,000 chance of being struck by lightning during your lifetime. Lightning can strike twice or more in the same spot. The Empire State Building in New York is struck by lightning about two dozen times annually. 7．You can measure how far you are from a lightning strike by counting the seconds between viewing the flash and hearing the bang, and then dividing by five. This approximates the mileage. Paragraphs 2 and 3______ A．Cloud-to-ground lightning occurring in the U. S. B．Types of lightning C．Cause of lightning D．Differences between thunder and thunderstorm E．Frequencies of thunderstorms occurring in the world and the U. S.F．Shock waves as thunder
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Dancing in the Streets If there is one thing certain to get Brazilians on their feet, it is the Rio Carnival (狂欢节). Held in Rio de Janeiro, the country’s biggest city, the carnival began on February 20 when the mayor gave key of the city to Rei Momo-the Lord of Misrule (无序之皇) On his orders, each year people turn the city into a paradise of dance and music. The following six days are so fun of parades, street dancing, fantastic clothes and partying (聚会) that many people forget about eating and sleeping. "It was the passion of the carnival that attracted me to Brazil and made me settle down in Rio. " said Bob Nadkarni, a British man who has lived in the city for several years. For many Brazilians, the centerpiece of the carnival is samba (桑巴舞) , a typical Brazilian dance. Every year, tens of thousands of visitors and locals show off their passion and energy in the streets, following the beat (节拍) of the Latin music. The climax to this street party is the float(彩车) parade, in which floats decorated with tons of fresh flowers by various samba schools and local communities move through the city. On the top of each float stands the candidate for the Drum Queen, who is chosen at the end of the party. While most people are free to enjoy the celebrations. Rio’s police officers have to keep a clear head. Following the murder of three officers in a gunfight early last week, the Brazilian Government has tightened security in Rio. The street fighting, robbery and sex crimes that accompany the carnival are very difficult to police. Carnivals began in ancient Rome as a celebration at which people fed wild wolves, in honor of the city’s founder who was said to have been raised by a she-wolf. Brazil gave new life to this tradition and so despite the troubles, the carnival will remain a symbol of the country’s culture. Which of the following statements is INCORRECT
B公司属于拥有大量资产、净资产为正值的上市公司，2004年度该公司财务报表的主要数据如下(单位：万元)：销售收入 1 000税后利润 100股 利 60股东权益 (200万股，每股面值1元) 1 000权益乘数 2该公司负债全部为有息长期负债，该公司2004年12月31日的股票市价为10元。要求计算：(1)2004年的可持续增长率。(2)2004年的市盈率和收入乘数。(3)若该公司处于稳定状态，其权益资本成本是多少(4)若该公司2004年的每股资本支出为0.6元，每股折旧与摊销0.4元，该年比上年营业流动资产每股增加0.2元。公司欲继续保持现有的财务比率和增长率不变，计算该公司股权价值。(5)与B公司所在行业相同的代表性公司有甲、乙两家公司。甲、乙两家公司的有关资料如下：资产净利率 权益乘数 每股市价 每股净资产甲公司 5.83% 2.4 12元 4元乙公司 6.22% 2 8元 2.5元请根据修正的市价/净资产比率模型评估B公司的价值。
Dancing in the Streets If there is one thing certain to get Brazilians on their feet, it is the Rio Carnival (狂欢节). Held in Rio de Janeiro, the country’s biggest city, the carnival began on February 20 when the mayor gave key of the city to Rei Momo-the Lord of Misrule (无序之皇) On his orders, each year people turn the city into a paradise of dance and music. The following six days are so fun of parades, street dancing, fantastic clothes and partying (聚会) that many people forget about eating and sleeping. "It was the passion of the carnival that attracted me to Brazil and made me settle down in Rio. " said Bob Nadkarni, a British man who has lived in the city for several years. For many Brazilians, the centerpiece of the carnival is samba (桑巴舞) , a typical Brazilian dance. Every year, tens of thousands of visitors and locals show off their passion and energy in the streets, following the beat (节拍) of the Latin music. The climax to this street party is the float(彩车) parade, in which floats decorated with tons of fresh flowers by various samba schools and local communities move through the city. On the top of each float stands the candidate for the Drum Queen, who is chosen at the end of the party. While most people are free to enjoy the celebrations. Rio’s police officers have to keep a clear head. Following the murder of three officers in a gunfight early last week, the Brazilian Government has tightened security in Rio. The street fighting, robbery and sex crimes that accompany the carnival are very difficult to police. Carnivals began in ancient Rome as a celebration at which people fed wild wolves, in honor of the city’s founder who was said to have been raised by a she-wolf. Brazil gave new life to this tradition and so despite the troubles, the carnival will remain a symbol of the country’s culture. According to the passage, Bob Nadkami is ______.
An Interesting Phenomenon Animals seem to have the sense to eat when they are hungry and they do not eat more than their bodies need. It has been demonstrated that rats will, when given a choice over a period of time, prefer water with vitamins to water without vitamins even though there is no difference in taste or smell between the two water bottles. When a fragrant flavor was added to the vitamin-enriched fluid, the rats did seem to develop a taste for it and kept drinking it, even after the vitamins were switched to the clear water. In time, however, they broke the habit and went back to where the necessary vitamins were. In a classic experiment, babies of 6 to 12 months old were placed in a cafeteria feeding arrangement, with a wide selection of baby food before them. They were given whatever food they pointed to or appeared interested in. We are told that at first they showed some unusual eating patterns, but that over a period of time they managed to select well-balanced diet. So, in selecting food, rats and babies do seem to know and act on what’s best for them. Apparently, there is a kind of "body wisdom", which humans soon lose. Most of us do not eat as wisely as we could. Many of our food preferences are culturally determined and influenced by long-established habits. Some people eat fox, dog and blackbirds, while we eat cows and pigs. So what people eat and how much they eat seems to be greatly influenced by what is going on around them. The expression "the habit" (para. 1, sentence 4) refers to drinking water which______
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