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本贴相关题目 OG-12-CR-1 (UTUN)

00:00:00

"Life expectancy" is the average age at death of the entire live-born population. In the middle of the nineteenth century, life expectancy in North America was 40 years, whereas now it is nearly 80 years. Thus, in those days, people must have been considered old at an age that we now consider the prime of life.

Which of the following, if true, undermines the argument above?

AIn the middle of the nineteenth century, the population of North America was significantly smaller than it is today.
BMost of the gains in life expectancy in the last 150 years have come from reductions in the number of infants who die in their first year of life.
CMany of the people who live to an advanced age today do so only because of medical technology that was unknown in the nineteenth century.
DThe proportion of people who die in their seventies is significantly smaller today than is the proportion of people who die in their eighties.
EMore people in the middle of the nineteenth century engaged regularly in vigorous physical activity than do so today.

正确答案: B

请教两道逻辑题。。。菜鸟一只，刚开始准备G不到一周

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moremildseven

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发表于 2011-4-21 22:37:37 | 显示全部楼层

the first one B
if the number of infants who die in their first year of life is calculated in the Life expectancy, life expectancy in the last 150 years was certain low.However, if today's life expectancy gains because the factor above diminishes, that is, Most of the gains in life expectancy in the last 150 years have come from reductions in the number of infants who die in their first year of life. therefore, we can not conclude that people must have been considered old at an gage that we now consider the prime of life.

the second one D
if there is as much advertising on many cable-television channels as there is on "free" television channels, it was not a bargain to subcribe the cable television.becanse the cable television and the free television are same