单选题People in Europe began to drink tea with milk because ______.

单选题Jet lag is back on the agenda for business travelers, especially as long-haul international traffic picks up again. There is endless advice online about jet lag. Drugs are frequently mentioned, and a recent favorite is Nuvigil, used to treat excessive sleepiness. Nuvigil's manufacturer, Cephablon, has so far not succeeded in obtaining government approval for its plan to market the drug as a remedy forjet lag. But the approach I hear most often from long-haul travelers involves diet and preparation. " Why would you take a pill that your body then has to shake off? " said Lynne Waller Scanlon, the author, with Charles F. Ehret, of Overcoming Jet Lag, which was a best seller in the mid-1980s but went out of print until she revised and republished it last year under a snappier title, The Cure for Jet Lag. The book lays out a treatment system for jet lag based on pre-trip diet and conditioning to reset the body's internal clock. The book suggests resetting the body clock so that it will be in sync with the time at the destination. One to three days before a trip, the authors suggest low-calorie meals. In flight, avoid or strictly limit alcohol, and use coffee or tea to persuade the body clock that it's daytime. If it's morning after flying all night, resist sleep and " flood your eyes with daylight " , they suggest. While all long-haul travel can cause normal fatigue, travel across time zones causes the body to react with the most pronounced effects of jet lag, including disorientation and a general sense of discomfort. In the last few years, the global airlines have put more emphasis on accommodating the need for in-flight sleep—at least in the business and first—class cabins, where international airlines earn most of their revenue. But at the same time, international airlines also promote extensive in-flight entertainment selections, as well as high-end menus, including quality wine lists, in premium classes. Indulging in these would seem to work against dietary treatment to combat jet lag. But Ms. Scanlon says recovery is nevertheless attainable. " What do you do if you can't implement this program ahead of the trip, or if you've blown it and had a complete debauch on the plane? " she said, " Well, when you get off that plane, you get on the program right away. It may not be perfect, but you will feel much, much better. /

单选题The word "omnipresent" in line 4, Par

单选题The word “schism” ( Line 3, Par

单选题In the tropical areas, ______.

单选题When enthusiasts talk of sustainable development, the eyes of most people glaze over. There is a whiff of sack-cloth and ashes about their arguments, which usually depend on people giving up the comforts of a modern economy to achieve some debatable greater good. Yet there is a serious point at issue. Modern industry pollutes, and it also seems to cause significant changes to the climate. What is needed is an industry that delivers the benefits without the costs. And the glimmerings of just such an industry can now be discerned. That industry is based on biotechnology. At the moment, biotech's main uses are in medicine and agriculture. But its biggest long-term impact may be industrial. Here, it will diminish demand for oil by taking the cheapest raw materials imaginable, carbon dioxide and water, and using them to make fuel and plastics. Plastics and fuels made in this way would have several advantages. They could accurately be called "renewables", since nothing is depleted to make them. They would be part of the natural carbon cycle, borrowing that element from the atmosphere for a few months, and returning it when they were burned or dumped. That means they could not possibly contribute to global warming. And they would be environmentally friendly in other ways. Bioplastics are biodegradable, since bacteria understand their chemistry and can therefore digest them. Biofuels, while not quite "zero emission" from the exhaust pipe (though a lot cleaner than petrol and diesel), would be cleaner overall even than the fuel-cell technology now being touted as an alternative to the internal-combustion engine. That is because making the hydrogen that fuel cells use is not an environmentally friendly process, and never will be—unless it, too, uses biotechnology. All this will, in the end, depend on costs. But these do not look unfavourable. Already, the price of bioplastics overlaps the top end of the petroleum-based plastics market. Bulk production should bring prices down, particularly when the raw materials are free. Meanwhile, ethanol would be a lot easier to introduce than fuel cells. Existing engines will run on it with minor tweaking, so there is no need to change the way cars are made. And since, unlike hydrogen, it is a liquid, the fuel-distribution infrastructure would not need radical change. The future could be green in ways that traditional environmentalists had not expected. Whether they will embrace that possibility, or stick to sack-cloth, remains to be seen.

单选题What does the author believe according to the passage?______

单选题Current Group, a Germantown-based technology firm, has taken over an ordinary looking house in Bethesda and turned it into a laboratory for smart-grid technology, the system the company believes will bring the nation's electricity grids into the digital age. In the front yard stands a utility pole hooked up to a special transformer that connects the power lines to high-speed Internet. Hundreds of sensors attached to the lines monitor how power flows through the home. That information is then sent back to the utility company. The process lets a utility more efficiently manage the distribution of electricity by allowing two-way communication between consumers and energy suppliers via the broadband network on the power lines. Based on data they receive from hundreds of homes, utilities can monitor usage and adjust output and pricing response to demand. Consumers can be rewarded with reduced rates by cutting back on consumption during peak periods. And computerized substations can talk to each other so overloaded circuits hand off electricity to those that axe not fully loaded, helping to prevent blackouts. Some utility companies have launched initiatives to give consumers data about their energy consumption habits in an effort to lower energy bills. Smart-grid technology takes such programs further by automating electricity distribution, which would make grids more reliable and efficient. By partnering with utilities, the company hopes to tap into $4.5 billion in stimulus grants intended to encourage smart-grid development. When he announced the funding, President Obama pointed to a project in Boulder, Colo., as an example of a successful smart-grid experiment. Current is one of the companies working on the project. Current's chief executive Tom Casey believes the technology will help utility companies better distribute electricity produced by renewable resources, such as solar panels or wind farms. "A smart grid's system can be paired up with the renewable resources so that when the renewable source is varying, the overall load can be varied as well," Casey told the House Select Committee on Energy Independence and Global Warming. "This will reduce or eliminate the need for backup coal or gas based power generation plants./

单选题What can be inferred from the passage about the agricultural sector of the economy after the Civil War?______

单选题It may not have generated much interest outside energy and investment circles, but a recent comment by Tidewater, Inc. president Dean Taylor sent earthquakes through the New Orleans business community. In June, Taylor told the Houston Chronicle that the international marine services company—the world's largest operator of ships serving the offshore oil industry—was seriously considering moving its headquarters, along with scores of administrative jobs, from the Crescent City to Houston, "We have a lot of sympathy for the city, " Taylor said. "But our shareholders don't pay us to have sympathy. They pay us to have resuits for them." It was the last thing the hurricane-scarred city needed to hear. Tidewater was founded here a little more than 50 years ago, and kept its main office in New Orleans throughout the oil bust of the-1980s and the following decades of industry consolidation, when dozens of energy firms all but abandoned New Orleans for greener pastures on the Texas coast. In the nearly two years since Hurricane Katrina ravaged the city, the pace of exodus has accelerated, complicating New Orleans' halting recovery; according to the local business weekly CityBusiness, the metropolitan area has lost 12 of the 23 publicly traded companies headquartered here, taking white-collar jobs, Corporate community support and sorely needed taxpayers with them—and threatening to leave the city even more dependent on a tourismbased economy than it was before the storm. Making matters worse, some observers say, is the city leadership's apparent indifference to the bloodletting. Just weeks after Hurricane Katrina in August 2005, Mayor Ray Nagin, then in the very early stages of a heated reelection bid, dismissed warnings that many companies, like displaced residents, might opt to relocate. Nagin said he hoped they would stay. "But if they don't," he said with typical glibness, "I'll send them a postcard. "The comment might have been written off as one of Nagin's many verbal missteps. But in the months that followed, the warnings turned out in many cases to be true, even as the city's rebuilding effort languished, infrastructure repairs limped along, the state reimbursement program for damaged homes faltered and the New Orleans' infamous crime rate made a sickening comeback. New Orleans "wasn't considered a great city for doing business before the storm. People were always dribbling out," says Peter Ricchiuti, a professor of economics at Tulane University. While many of the companies that made it through the storm could stand to benefit from the city's recovery, he says, Katrina may have hastened the loss of high-paying energy jobs. "We're losing the white-collar jobs and keeping the blue-collar jobs," he says. "We're becoming much more of a blue-collar oil industry." One of the latest examples is Chevron Corp. , which is building new offices in the northern suburbs, 40 miles north of the city across Lake Pontchartraln, and plans to transfer 550 employees from New Orleans to Covington by the end of the year. That would take well-paid people out of downtown New Orleans, a move that will impact the central business district's economy. "We made the decision in May, 2006, when our employees were making important housing decisions," says Qi Wilson, a Chevron spokesperson. The company; like many employees, decided the north shore offered better security should another hurricane strike, along with fewer of the post-Katrina headaches that still plague the city. The move "will make it easier to retain the talent we have, and to attract new talent," Wilson says.

单选题Energy will be one of the defining issues of this century. One thing is clear: the era of (1) oil is over. What we all do next will determine how well we meet the energy needs of the entire world in this century and (2) . Demand is soaring like (3) before. As populations grow and economies (4) , millions in the developing world are enjoying the benefits of a lifestyle that (5) increasing amounts of energy. In fact, some say that in 20 years the world will (6) 40% more oil than it does today. At the same time, many of the world's oil and gas fields are (7) . And new energy discoveries are mainly occurring in places where resources are difficult to (8) , physically, economically and even politically. When growing demand meets (9) supplies, the result is more (10) for the same resources. We can wait until a crisis forces us to do something. (11) we can (12) to working together, and start by asking the (13) questions.- How do we meet the energy needs of the developing world and those of industrialized nations? What role will renewables and (14) energies play? What is the best way to protect our environment? How do we accelerate our conservation efforts? (15) actions we take, we must look not just to next year, (16) to the next 50 years. At Chevron, we believe that innovation, collaboration and conservation are the (17) on which to build this new world. We cannot do this alone. Corporations, governments and every citizen of this planet must be part of the solution as (18) as they are part of the problem. We (19) scientists and educators, politicians and policy-makers, environmentalists, leaders of industry and each one of you to be part of (20) the next era of energy.