Which of the following statements is NOT true according to the passage？
A. In the past, people sometimes plugged their ears to fight against the offending noise.
B. An active noise-cancellation system follows the principles of a wave being flattered by meeting its exact opposites.
C. The first active noise-cancellation system was made in the 1930s.
D. Active noise-cancellation systems are now available on the market.
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Let me take you on a trip towards death. (Sentence 3, Paragraph 1) indicates ______.
A. general anesthesia is dangerous
B. the operation will pain the patient m death
C. the operation will kill the patient
D. the anesthetist is speaking in a joking way
Why has President Bush's ban on lie detector evidence in military courts in 1991 been over-turned？
A. Because lie detection is surrounded by uncertainties.
Because it restricts the defendant' rights to prove that they are innocent.
C. Because 12 U.S. states also allow lie detection evidence to be heard in courts.
D. Because federal judges from the Supreme Court make their decisions on the basis of lie detection.
A．experimentsB．trial and errorC．factsD．studies
A. experiments
B. trial and error
C. facts
D. studies
某产品划分为4个功能区，采用环比评分法得到的功能暂定重要性系数见下表。
则功能区F3重要性系数为()。
A. 0.17
B. 0.35
C. 0.36
D. 0.42
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