[单项选择]In the U.S. ______ percent of the infants with AIDS are white.


A. 91
B. 9
C. 40
D. 20

[单项选择]In the U.S. ______ percent of the infants with AIDS are white.


A. 91
B. 9
C. 40
D. 20

[单项选择]

Passage Two
Having no language, infants cannot be told what they need to learn. Yet by the age of three they will have mastered the basic structure of their native language and will be well on their way to communicative competence. Acquiring their language is a most impressive intellectual feat. Students of how children learn language generally agree that the most remarkable aspect of this feat is the rapid acquisition of grammar. Nevertheless, the ability of children to conform to grammatical rules is only slightly more wonderful than their ability to learn words. It has been reckoned that the average high school graduate in the United States has a reading vocabulary of 80,000 words, which includes idiomatic expressions and proper names of people and places. This vocabulary must have been learned over a period of 16 years. From the figures, it can be calculated that the average child learns at a rate of about 13 new words per day. Clearly a le
A. their ability
B. reading vocabulary
C. idiomatic expression
D. learning process

[单项选择]It is discovered that infants of four weeks old are already able to recognize subtle difference in language sounds.
A. diverse
B. evident
C. minute
D. peculiar

[单项选择]A) childs C) boys
B) infants D) kids


A. childs
B. infants
C. boys
D. kids

[单项选择]A 12 percent coupon bond with semiannual payments is callable in 5 years. The call price is $1120. If the bond is selling today for $1110, what is the yield-to-call

[单项选择]Assume that the reserve requirement is 20 percent and banks currently have no excess reserves. If excess reserves stay at zero and the Federal Reserve buys $100 million of Treasury bills from the public, the money supply would increase by:（）
A. $20 million.
B. $100 million.
C. $500 million.

[单项选择]Their production increased by 15 percent over that of the previous year.（）
A. 他们的产量增加到前年的百分之十五。
B. 跟前年比，他们的产量又—上升了十五个百分点。
C. 他们的产量跟前一年比，增加到百分之十五。
D. 他们的产量比上一年增长了百分之十五。