The selection says that computers play an essential roles in （）.
A. automation processes
B. mathematical computations
C. traffic control
D. the development of mathematical theory
They are as closely related as the lips and teeth, so to speak.
2（）
A. easy
B. short
C. high
D. difficult
Important ______ his discovery was, it was regarded as a matter of no account in his time.
A. to
B. for
C. though
D. although
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