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[主观题]

After observing that bacteria took up toxic dyes, Paul Ehrlich discovered arsphenamine, the first antibiotic.

A、Right

B、Wrong

C、Not mentioned

D、----

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第1题

听力原文: Two workers died and six were badly injured yesterday after apparently inhaling toxic gas at a waste treatment plant in western Japan. A police spokesman said the men were using a mixer tank containing chemicals to treat industrial waste when the accident occurred at the factory in Fukushima. One man fell into the tank and colleagues trying to fish him out collapsed almostimmediaely.

What were the men doing according to the police?

A.They were treating industrial waste.

B.They were tanking industrial waste.

C.They were tanking chemicals.

D.They were using a tank to mix chemicals.

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第2题

Text 2We’re moving into another era, as the toxic effects of the bubble and its grave consequences spread through the financial system. Just a couple of years ago investors dreamed of 20 percent returns forever. Now surveys show that they’re down to a “realistic”8 percent to 10 percent range.

But what if the next few years turn out to be below normal expectations? Martin Barners of the Bank Credit Analyst in Montreal expects future stock returns to average just 4 percent to 6 percent. Sound impossible? After a much smaller bubble that burst in the mid-1960s Standard & Poor’s 5000 stock average returned 6.9 percent a year (with dividends reinvested) for the following 17 years. Few investors are prepared for that.

Right now denial seems to be the attitude of choice. That’s typical, says Lori Lucas of Hewitt, the consulting firm. You hate to look at your investments when they’re going down. Hewitt tracks 500,000 401 (k) accounts every day, and finds that savers are keeping their contributions up. But they’re much less inclined to switch their money around. “It’s the slot-machine effect,” Lucas says. “People get more interested in playing when they think they’ve got a hot machine”—and nothing’s hot today. The average investor feels overwhelmed.

Against all common sense, many savers still shut their eyes to the dangers of owning too much company stock. In big companies last year, a surprising 29 percent of employees held at least three quarters of their 402 (k) in their own stock.

Younger employees may have no choice. You often have to wait until you’re 50 or 55 before you can sell any company stock you get as a matching contribution.

But instead of getting out when they can, old participants have been holding, too. One third of the people 60 and up chose company stock for three quarters of their plan, Hewitt reports. Are they inattentive? Loyal to a fault? Sick? It’s as if Lucent, Enron and Xerox never happened.

No investor should give his or her total trust to any particular company’s stock. And while you’re at it, think how you’d be if future stock returns—averaging good years and bad—are as poor as Barnes predicts.

If you ask me, diversified stocks remain good for the long run, with a backup in bonds. But I, too, am figuring on reduced returns. What a shame. Dear bubble, I’ll never forget. It’s the end of a grand affair.

第26题:The investors’ judgment of the present stock returns seems to be _____.

[A] fanciful

[B] pessimistic

[C] groundless

[D] realistic

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第3题

The toxic plasticizer DEHP, was reportedly discovered in imported cosmetics.

A.Right

B.Wrong

C.Not mentioned

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第4题

The toxic plasticizer DEHP, was reportedly discovered in imported cosmetics.

A.Right

B.Wrong

C.Not mentioned

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第5题

The toxic plasticizer DEHP, was reportedly discovered in imported cosmetics.

A.Right

B.Wrong

C.Not mentioned

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第6题

Now medical researchers are discovering a truism: "alcohol and tobacco do not mix." These two substances, both dangerous to health, act synergistically, each making the other more powerful and thereby causing worse damage than either would do alone.

Because of this interaction, the person who both smokes and drinks heavily may be at a greater risk of becoming ill than one who drinks like a fish, but never smokes or who smokes like a chimney, but never drinks. To get an idea of how this synergism may work, consider what happens when a smoker lights up a cigarette. With each puff he inhales at least 4,000 different chemicals. These include toxic hydrogen-cyanide, carbon monoxide and nitrogen-dioxide gases, and four dozen compounds such as benzo pyrene and radioactive polonium 210 . All are known as carcinogens. Most chemical vapors in tobacco smoke get deposited in the mouth, nose, throat and lungs in a coating called tar. It is in this tar that most of the cancer--inducing potential of tobacco smoke lies. Then in a scenario typical of chronic heavy drinkers--most of whom also smoke--our smoker feels thirsty and washes down that smoke coating in his mouth and throat with whisky. The alcohol in his drink is not in itself a carcinogen, but it may act as a solvent, dissolving the tar-taped tobacco poisons, and easing the transport of carcinogens across membranes.

Our smoker continues to drink. Soon he lights another cigarette and inhales deeply. Behind his embattled lungs, meanwhile, his liver has gone on full alert to save his life. The three-pound chemical factory, which cleans most toxins from the bloodstream, reacts to alcohol as a foreign substance and metabolizes 95 percent of it into other chemicals. But in turning its energy to clearing just one-half ounce of pure alcohol--the amount in a standard drink--per hour from our drinking smoker's blood, the liver's other metabolic functions suffer a sharp decrease. Poisons from tobacco smoke that otherwise would be removed from his blood within minutes are now allowed to flood his body for hours or days, depending on how much alcohol the liver must dispose of.

The person who smokes one or two packs of cigarettes a day loses on average six to eight percent of his blood's oxygen carrying capacity. If our heavy smoker's use of alcohol has led to alcoholism, he is probably malnourished. This malnourishment compounds problems he is having with insufficient oxygen. His brain cells are dying from it.

The synergistic effect of alcohol and tobacco may deliver a powerful blow to the cardiovascular system as well as the upper respiratory tract. For those prone to hypertension who drink more than two ounces of alcohol a day, high blood pressure is common and with it the increased risk of stroke and heart attack. For hypertensives who combine smoking and drinking, the risks are even greater.

Which of the following can be the best title of this passage?

A.Dead Mixer=Alcohol+ Tobacco.

B.Alcohol and Tobacco Are Dangerous to Health.

C.Tobacco Contains a Lot of Toxic Compounds.

D.Interaction of the Alcohol and Tobacco.

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第7题

To prevent a repetition of this dreadful occurrence, we must discover the element in the food that was served.

A.unknown

B.toxic

C.kind

D.shameful

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