Ⅰ.every non-key attribute is functionally dependent on the full set of primary key attributes.
Ⅱ.no non-key attributes exist in the relation.
Ⅲ.the primary key consists of only one attribute.
A. Ⅰ only
B. Ⅰ and Ⅱ only
C. Ⅰ and Ⅲ only
D. any of them
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What does the word "adopt" (Line 2, Para 2) mean in the passage？
A. take
B. adjust
C. adapt
D. expert
"A large extended family" is probably ______.
A. a rich family group
B. a family group which includes uncles, aunts, grandparents, as well as parents and children
C. a family business
D. a family that has many children
What can be inferred about Votefortheworst.com from the text？
A. it is a website whose founder Howard Stern is a popular figure.
B. it valuates the Idol contestants in the same way as the TV producers.
C. it is powerful enough to influence the outcome of American Idol.
D. it is almost as popular as the American Idol official website.
By referring to the Nikkei 225, the author wants to imply that ______.
A. investors will keep buying until prices reach stratospheric levels.
B. the universally accepted opinion among American investors isn't perfect.
C. the slide of Nikkei 225 has been longer and deeper than ever before.
D. Japanese investors have to wait 50-60 years to earn a positive real return.
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