题目内容
There are no permanent inhabitants in Antarctica because
查看答案
搜索结果不匹配？点我反馈
更多问题
根据材料请回答 16～22 题
The U.S.food supply is the most varied and abundant in the world.Americans spend a smaller share of their disposable income(可支配收入)on food than citizens of any other country and choose from an average of 50,000 different food products on a typical outing to the supermarket.In 1994, the fowl supply provided an estimated 3, 800 calories (卡路里) per person per day, enough to supply every American with more than one and a half times their average daily energy needs.Given this abundance, few of the Nations resources have traditionally been devoted to measuring or reducing food waste.
In recent years, growing concern about hunger, resource conservation, and the envi-ronmental and economic costs associated with food waste have raised public awareness of food loss.This in turn has accelerated public and private efforts to make better use of a-vailable food supplies by recovering safe and nutritious (有营养的)food that would other-wise be wasted.
Of course, not all food that is lost is suitable for consumption.Some losses - like the condemnation of diseased animals at the slaughtering house (屠宰场), or the discard of rotten fruit from the produce shelf at the supermarket are necessary to ensure the safety and health of the U.S.food supply.Such foods are not recoverable for human, use.
Likewise, plate fragments are appropriately discarded at eating establishments out of health considerations.In addition, not all food that is 10st is economically recoverable.Food recovery efforts are often limited by financial restraint.s that make it difficult-to match recovered food with potential recipients.
Nevertheless, large quantities of healthy, edible food are lost at every stage of the marketing system.Example of such losses include meats, bread, and other foods prepared by a restaurant or hotel but never served and the discard of defected or over-ripe produce, which may be difficult to sell out for some reasons, but are otherwise nutritious and safe.
第 16 题 The problem in America that the author is talking about in this passage is large a-mounts of food are lost in American.
A．relationshipB．differenceC．similarityD．correlation
根据材料请回答 23～30 题
Lie detectors (测谎仪)are widely used in the United States to find out whether a per-son is telling the truth or not.Polygraphists, the person who operate them, claim that they can establish guilt by detecting physiological changes that accompany emotional stress.The technique adopted is to ask leading questions such as: "Did you take the mo-ney？" or "Where did you hide the money？", mixed in with neutral questions, and measure the subject's electrical resistance in the palm or changes in his breathing and heart rate.Such apparatus has obtained widespread recognition.
Whether lie detectors will ever be adopted on a similar scale in Britain is still a matter of opinion.At first sight, it appears obvious that any simple, reliable method of convic-ting guilty people is valuable, but recent research sponsored by the U.S.Office of Public Health not only raises doubts about how lie detectors should be.used but also makes it questionable whether they should be employed at all.
The point is that, apart from many of the polygraphists being unqualified, the tests themselves are by no means free from error, primarily because they discount human imagi-nation and ingenuity.Think of all those perfectly innocent people, with nothing to be a-fraid of, who blush and stammer when a customs officer asks them if they have anything to declare.Fear, and a consequently heightened electrical response, may not be enough to establish guilt.It depends on whether the subject is afraid of being found out or afraid of being wrongfully convicted.
On the other hand, the person who is really guilty and whose past experience has pre-pared him for such tests can distort the results by anticipating the crucial questions or de-liberately giving exaggerated responses to neutral ones!
The success rate of up to 90% claimed for lie detectors is misleadingly attractive.If we refer such a figure to a company with 500 employees, twenty of whom are thieves, the lie detector could catch 18 of them but in doing so would place 32 innocent employees un-der suspicion.The problem for the management would therefore become one of deciding how much industrial unrest they are prepared to cause in order to eliminate theft.What concerns research workers even more, of course, is the fact that a certain number of in no-cent people are bound to be convicted of crimes that they have not committed.
第 23 题 Paragraph 1__________
根据材料请回答 30～34
Sunbath and Skin Cancer
In the summer, millions of Americans will offer up their bodies to the sun rays.A tan indicates health and beauty, and most sun worshippers will sacrifice a lot to achieve it, in-eluding themselves．
With each hour，the sun’s ultraviolet radiation(紫外线)produces irreversible(不可逆的)damage，hastening the development of unsightly wrinkles．And with each year OII the beach or rooftop，the sunbather increases his risk of getting skin cancer．Skin cancer is by far the most common form. of cancer．An estimated 400，0()0 new cases will be blamed this year in the United States．and almost all of them can be blamed on over-exposure to the sun．
Fortunately，most of these cancers are highly curable．I3ut they can he disfiguring arm take time to treat．For that reason，sun worshippers should treat deity with a good deal of awe(敬畏)．Sunburn，of course，is the initial hazard posed by UV radiation．Prolonged exposure to UV，however，interferes with the production of collagen fibers(胶原纤维)in the dermis(真皮层)，causing the skin to lose elasticity(弹性)and creating premature wrinkles．Further deterioration(恶化)of the dermis deprives t he epidermis(表皮层)of nutrition and causes it to become thin and dry．
Cancer is UV’s final result．Shortwave radiant energy，especially from the UV B band，breaks the strands(股、缕)of DNA．Enzymes(酶)work constantly t()rearrange the DNA into proper sequence．but with repeated UV exposure，the repair process may even—tually break down．Then the mutant(变异的)DNA may produce a colony of cancer cells．But skin cancer may be avoided with a good dose of common sense．People with fair skin and blue eyes who burn easily stand the highest risk．Special danger spots are the parts of the body most constantly exposed to the sun，such as the cheeks，nose，lower lip and the ears．People who have already developed precancerous(癌变前的)lesions(伤害)or had one skin-cancer growth stand a greatly increased chance of developing others．
Dermatologists(皮肤科医生)recommend avoiding the sun when it is most intense be—tween 11 a．m．and 3 P．m．Anyone who insists on sunbathing should use a good sun screen．These lotions and salves(药膏)contain chemicals that block out the burning UVB radiation while permitting the tanning rays to reach the skin．
第 30 题 According to the passage，over—exposure to the sun may result in
微信支付 
支付宝支付