| Nearly two thousand years have passed
since a census decreed by Caesar Augustus became part of the greatest story ever
told. Many things have changed in the intervening years. The hotel industry
worries more about overbuilding than overcrowding, and if they had to meet an
unexpected influx, few inns would have a manger to accommodate the weary guests.
Now it is the census taker that does the traveling in the fond hope that a
highly mobile population will stay put long enough to get a good sampling.
Methods of gathering, recording, and evaluating information have presumably been
improved a great deal. And where then it was the modest purpose of Rome to
obtain a simple head count as an adequate basis for levying taxes, now batteries
of complicated statistical series furnished by governmental agencies and private
organizations are eagerl A. mobility B. wealth C. population D. census takers [单项选择]Although recent years have seen substantial reductions in noxious pollutants from individual motor vehicles, the number of such vehicles has been steadily increasing. Consequently more than 100 cities in the United States still have levels of carbon monoxide, particulate matter, and ozone (generated by photochemical reactions with hydrocarbons from vehicle exhaust) that exceed legally established limits. There is a growing realization that the only effective way to achieve further reductions in vehicle emissions--short of a massive shift away from the private automobile—is to replace conventional diesel fuel and gasoline with cleaner-burning fuels such as compressed natural gas, liquefied petroleum gas, ethanol, or methanol.
All of these alternatives are carbon-based fuels whose molecules are smaller and simpler than those of gasoline. These molecules burn mom cleanly than gasoline, in part because they have fewer, if any, carbon-carbon bonds, and the hydrocarbons they do emit are A. countering a flawed argument that dismisses a possible solution to problem B. reconciling contradictory points of view about the nature of a problem C. identifying the strengths of possible solutions to a problem D. discussing a problem and arguing in favor of one solution to it 我来回答: 提交
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