When did the Chinese invent the Compass？
A. In 1492．
B. In the thirteenth century A．D．
C. In A．D．80．
D. At least 2000 years ago．
Computers can understand clear and carefully dictated speech more accurately than
A. Right
B. Wrong
C. Not mentioned
Besides English, French is another frequently used language of science．
A. Right
B. Wrong
C. Not mentioned
The nerve fibers connecting these light-sensitive elements--to the brain____.
A. all work together
B. help each other
C. work independently
D. work in small groups
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