[单项选择]The population which is top-heavy with older people poses a problem to ______.
A. the government
B. the economy
C. the workforce
D. All of the above.

[单项选择]The population which is top-heavy with older people poses a problem to______.
A. the government
B. the economy
C. the workforce
D. all of the above

[单项选择]The researchers found the age at which young people first fall ______ to bullies seems to determine how much it affects them.
A. sacrifice
B. short
C. witness
D. victim

[单项选择]In which of the following years did the poor people constitute the largest proportion of the American population
A. 1973.
B. 1987.
C. 1969.
D. 1983.

[单项选择]

In our population, which is now about 167 million, it is estimated there are more than 33 million people with I. Q. ’s below 90; it is a disturbing thought that these people will never, at any age, read much more than comic books, newspaper headlines, and the simplest of best sellers, nor will they be able to make intelligent judgments on any complicated, important national or international problem. The intellectuals, of course, are at the other end of the scale, they are people with I. Q. ’s of 130 or more, and there are slightly more than five million. From130 to the top of the scale, there are only 2.1 million people. Careful tests have shown that at least half of these high I.Q. people are never discovered, do not go to college, and live out their lives in humble, even though usually respected, occupations. The identified intellectual, therefore, will at best be only one person in 46, and is more likely to be one person in 150. It is not surprising that he feels a
A. disapprove of the mental activities of people at any other level
B. be unconcerned about the mental activities of people at other level
C. have a deep sympathy for people with low I. Q.
D. find a stimulating challenge in the mental activities of the intellectual

[单项选择]Which statement is TRUE about population increase
A. There might be an increase of 2.2 billion persons from now to the year 2000.
B. About 50,000 babies are born every, six hours at present.
C. Between 8000 B.C. and the present, the population increase is about 80,000,000 persons each year.
D. The population increased faster between 8000 B. C. and 1650 than between 1650 and the present.

[单项选择]Most of the older civilizations which flourished during the fifth century B.C.are died out（）.
A. they have died out
B. has died out
C. have died out
D. they had died out

[单项选择]Which city has the biggest population in Canada
A. Toronto.
B. Vancouver.
C. Quebec.
D. Ottawa.

[单项选择]The population rose fast in the places which had the most ______ soils such as on the flood plains of great rivers.
A. fertile
B. abundant
C. rich
D. barren