[单项选择]A fireman discovered the______of the fire.
[A] truth [B] reason [C] cause [D] fact

[单项选择]A fireman discovered the （　） of the fire.
A. truth
B. reason
C. cause
D. fact

[单项选择]t_R
A. 峰面积
B. 峰高
C. 保留时间
D. 峰宽
E. 半高峰宽

[单项选择]The brave fireman had fought for days before they managed to ______ the forest fire.
A. put on
B. put up with
C. put off
D. put out

[单项选择]

RolfBlum, a Wuppertal fireman, knows that life and death are just seconds apart.
When fire can kill within a few breaths, anything which gives him a little extra time is vital.
Du Pont has spent years working with fire authorities to help give them those extra seconds.
The result is a lightweight, fire resistant fibre: NOMEX Ⅲ.
A suit of NOMEX III allows firemen to work closer to a fire, and enabled Roll Blum and his colleagues to rescue a little girl. Without it, he wouldn’t have been able to reach her.
NOMEX III is now standard wear for the fire brigades of many cities including Frankfurt, London and Milan, providing those vital extra seconds which could last a lifetime.
Safety is just one area in which Du Pont is making important breakthroughs. Through Research & Development investment in excess of $1.3 billion each year and close cooperation with specialists in areas such as industry, agriculture and medicine, Du Pont
A. fire can kill anyone very quickly.
B. fire does not kill easily.
C. fire always kills.
D. fire is impossible to fight.

[单项选择]t_R表示
A. 相对保留时间
B. 相对标准偏差
C. 比旋度
D. 比移值
E. 半衰期

[填空题]The fireman rescued the children from the（）(burn) house at the risk of their own Jives.

[填空题]The fireman rushed into the burning home, (mind)（）of the danger.

[单项选择]Marine archaeologists recently discovered underwater in an ancient Mediterranean harbor several hundred ceramic objects, dating back approximately 4,000 years. Although any remnants of a ship’s wooden frame would have long ago decayed, the quantity and variety of the ceramics discovered in the initial investigation led the archaeologists to hypothesize that they had discovered an approximately 4,000-year-old shipwreck.
Which of the following, if true, gives the strongest support to the archaeologists’ hypothesis
A. Marine archaeologists have discovered a 3,000-year-old shipwreck in another ancient Mediterranean harbor.
B. The rate at which wood decays when submerged in water varies greatly with the type of wood involved.
C. Two confirmed shipwrecks, approximately 3,500 and 3,000 years old, respectively, have been discovered in the same harbor in which the ceramic objects were discovered.
D. The ceramics discovered in the harbor are similar to ceramics found in several other ancient Mediterranean harbors.
E. (E) Broke ship’s fittings, approximately 4,000 years old, were discovered on the seabed among the ceramic objects.

[填空题]Some researchers have discovered that chimpanzees have a hallmark of human culture.

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