The World"s Longest BridgeRumor has it that a legendary six-headed monster lurks in the deep waters of the Tyrrhenian Sea between Italy and the island of Sicily. 1 When completed in 2010, the world"s longest bridge will weigh nearly 300,000 tons—equivalent to the iceberg that sank the Titanic—and stretch 5 kilometers long. "That"s nearly 50 percent longer than any other bridge ever built." says structural engineer Shane Rixon. 2 They"re suspension bridges, massive structures built to span vast water channels or gorges. A suspension bridge needs just two towers to shoulder the structure"s mammoth weight, thanks to hefty supporting cables slung between the towers and anchored firmly in deep pools of cement at each end of the bridge. The Messina Strait Bridge will have two 54,100-ton towers, which will support most of the bridge"s load. The beefy cables of the bridge, each 1.2 meter in diameter, will hold up the longest and widest bridge deck ever built.When construction begins on the Messina Strait Bridge in 2005, the first job will be to erect two 370 meter-tall steel towers. 3 Getting these cables up will be something. It"s not just their length—totally 5.3 kilometers—but their weight. 4 After lowering vertical "suspender" cables from the main cables, builders will erect a 60 meter-wide 54,630-ton steel roadway, or deck—wide enough to accommodate 12 lanes of traffic. The deck"s weight will pull down on the cables with a force of 70,500 tons. In return, the cables yank up against their firmly rooted anchors with a force of 139,000 tons—equivalent to the weight of about 100,000 cars. Those anchors are essential. 5 A. Some environmentalists are against the project on biological grounds.B. What do the world"s longest bridges have in commonC. If true, one day you might spy the beast while zipping (呼啸而过) across the Messina Strait Bridge.D. They"re what will keep the bridge from going anywhere.E. The second job will be to pull two sets of steel cables across the strait, each set being a bundle of 44,352 individual steel wires.F. They will tip up the scales at 166,500 tons—more than half the bridge"s total mass.
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代谢性酸中毒患者会出现
A. 间停呼吸
B. 潮氏呼吸
C. 呼吸浅快
D. 库氏呼吸
E. 呼吸浅慢
Heat Is KillerExtremely hot weather is common in many parts of the world. Although hot weather just makes most people feel hot, it can 1 serious medical problems—even death. Floods, storms, volcano eruptions and other natural 2 kill thousands of people every year. So 3 extreme heat. Experts say heat may be nature"s deadliest killer. Recently, extreme heat was blamed 4 killing more than one hundred people in India. It is reported that the total heat of a hot day or several days can 5 health. Several hot days are considered a heat wave. Experts say heat waves often become dangerous when the nighttime temperature does not 6 much from the highest daytime temperature. This causes great stress on the human body.Doctors say people can do many things to 7 themselves from the dangers of extreme heat. Stay out of the sun, if possible. Drink lots of cool water. Wear light colored clothing made 8 natural materials; avoid wearing synthetic clothing. Make sure the clothing is 9 , permitting freedom of movement. And learn the danger 10 of the medical problems, such as headache and vomiting, that are linked to heat. Most people suffer only muscle pain as a(n) 11 of heat stress. The pain is a 12 that the body is becoming too hot. Doctors say those suffering headache or muscle pain should stop all activity, rest in a cool place and drink cool liquids. Do not return to physical 13 for a few hours because more serious conditions could develop.Doctors say some people face an 14 danger from heat stress. Such persons have a weak or damaged heart, high blood pressure, or other problems of the blood system.Hot weather also increases dangers for people who must take 15 for high blood pressure, poor blood flow, nervousness or depression.
A. influence
B. result
C. effect
D. view
Heat Is KillerExtremely hot weather is common in many parts of the world. Although hot weather just makes most people feel hot, it can 1 serious medical problems—even death. Floods, storms, volcano eruptions and other natural 2 kill thousands of people every year. So 3 extreme heat. Experts say heat may be nature"s deadliest killer. Recently, extreme heat was blamed 4 killing more than one hundred people in India. It is reported that the total heat of a hot day or several days can 5 health. Several hot days are considered a heat wave. Experts say heat waves often become dangerous when the nighttime temperature does not 6 much from the highest daytime temperature. This causes great stress on the human body.Doctors say people can do many things to 7 themselves from the dangers of extreme heat. Stay out of the sun, if possible. Drink lots of cool water. Wear light colored clothing made 8 natural materials; avoid wearing synthetic clothing. Make sure the clothing is 9 , permitting freedom of movement. And learn the danger 10 of the medical problems, such as headache and vomiting, that are linked to heat. Most people suffer only muscle pain as a(n) 11 of heat stress. The pain is a 12 that the body is becoming too hot. Doctors say those suffering headache or muscle pain should stop all activity, rest in a cool place and drink cool liquids. Do not return to physical 13 for a few hours because more serious conditions could develop.Doctors say some people face an 14 danger from heat stress. Such persons have a weak or damaged heart, high blood pressure, or other problems of the blood system.Hot weather also increases dangers for people who must take 15 for high blood pressure, poor blood flow, nervousness or depression.
A. warning
B. inference
C. need
D. guidance
Heat Is KillerExtremely hot weather is common in many parts of the world. Although hot weather just makes most people feel hot, it can 1 serious medical problems—even death. Floods, storms, volcano eruptions and other natural 2 kill thousands of people every year. So 3 extreme heat. Experts say heat may be nature"s deadliest killer. Recently, extreme heat was blamed 4 killing more than one hundred people in India. It is reported that the total heat of a hot day or several days can 5 health. Several hot days are considered a heat wave. Experts say heat waves often become dangerous when the nighttime temperature does not 6 much from the highest daytime temperature. This causes great stress on the human body.Doctors say people can do many things to 7 themselves from the dangers of extreme heat. Stay out of the sun, if possible. Drink lots of cool water. Wear light colored clothing made 8 natural materials; avoid wearing synthetic clothing. Make sure the clothing is 9 , permitting freedom of movement. And learn the danger 10 of the medical problems, such as headache and vomiting, that are linked to heat. Most people suffer only muscle pain as a(n) 11 of heat stress. The pain is a 12 that the body is becoming too hot. Doctors say those suffering headache or muscle pain should stop all activity, rest in a cool place and drink cool liquids. Do not return to physical 13 for a few hours because more serious conditions could develop.Doctors say some people face an 14 danger from heat stress. Such persons have a weak or damaged heart, high blood pressure, or other problems of the blood system.Hot weather also increases dangers for people who must take 15 for high blood pressure, poor blood flow, nervousness or depression.
A. food
B. medicine
C. water
D. meal