The United States population is growing older. In 1987, 12 percent of Americans were 65 years old or older, compared with 8 percent in 1950. Population experts at the U.S. Bureau of the Census expect this percentage to continue to rise gradually, reaching 14 percent in 2010, then to skyrocket during the next 20 years, reaching 21 percent by 2030. This "graying of America" has generated concerns about whether the best really is yet to be, about how well off tomorrow’s elderly will be. There also are questions about the impact of an aging population on the rest of society.
The graying of America has two causes. First, advances in medical care have enable people to live longer. In the United States in 1900, the average life expectancy at birth was 47.7 years. By 1985, the latest year for which figures are available, it has climbed to 74.7 years.
Second, the U.S. birthrate rose in the mid-1900s, interrupting a long, slow decline. A dramatic increase oc
A. To bring attention to the needs of the elderly.
B. To contrast birth rates and life expectancy rates.
C. To explain how and why the American population is aging.
D. To show the percentages of age groups in general population.
The United States population is growing older. In 1987, 12 percent of Americans were 65 years old or older, compared with 8 percent in 1950. Population experts at the U.S. Bureau of the Census expect this percentage to continue to rise gradually, reaching 14 percent in 2010, then to skyrocket during the next 20 years, reaching 21 percent by 2030. This "graying of America" has generated concerns about whether the best really is yet to be, about how well off tomorrow’s elderly will be. There also are questions about the impact of an aging population on the rest of society.
The graying of America has two causes. First, advances in medical care have enable people to live longer. In the United States in 1900, the average life expectancy at birth was 47.7 years. By 1985, the latest year for which figures are available, it has climbed to 74.7 years.
Second, the U.S. birthrate rose in the mid-1900s, interrupting a long, slow decline. A dramatic increase oc
A. 1970-1990.
B. 1990-2010.
C. 2010-2030.
D. 2030-2050.
The population of the United States is only 6% the world’s population, but Americans (1) one third of all the energy (2) in the world. This fact alone says that Americans need to use less energy. And because the price of energy had been rising very rapidly (3) the limited supplies of oil in particular, Americans are becoming aware to the need to (4) energy. In California we have a California Energy Commission which has set up in the past five years to (5) plan for our future energy rise. We have (6) laws in California to help us conserve energy. First of all, our houses in California have been very (7) of energy in the past. They were not (8) very carefully and so the heat would go out of the house very rapidly. Now we require that the homes have a (9) level of insulation, and so the homes built now are much more (10)
(11) , in transportation (12) a large percentage of oil
A. staged
B. composed
C. developed
D. devised
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