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In Greenland, Ice and Instability
by Andrew C. Revkin, excerpt from The New York Times January 8, 2008
The ancient frozen dome cloaking Greenland is so vast that pilots have crashed into what they thought was a cloud bank spanning the horizon. Flying over it, you can scarcely imagine that it could erode fast enough to dangerously raise sea levels any time soon.
Along the flanks in spring and summer, however, the picture is very different. For an increasing number of warm years, a network of blue lakes and rivulets of melt-water has been spreading ever higher on the icecap.
The melting surface darkens, absorbing up to four times as much energy from the sun as snow, which reflects sunlight. Natural drainpipes called moulins carry water from the surface into the depths, in some places reaching bedrock.
The process slightly, but measurably, lubricates and accelerates the grinding passage of ice towards the sea.
Most important, many glaciologists say, is the break-up of huge semi-submerged clots of ice where some large Greenland glaciers, particularly along the west coast, squeeze through fiords as they meet the warming ocean. As these passages have cleared, this has sharply accelerated the flow of many of these creeping, corrugated and frozen rivers.
Some glaciologists fear that the rise in seas in a warming world could be much greater than the upper estimate of about 60 centimetres this century made by the Intergovernmental Panel on Climate Change last year. (Seas rose less than 30 centimetres last century.)
The panel&39;s assessment did not include factors known to contribute to ice flows but not understood well enough to estimate with confidence. SCIENTIFIC scramble is under way to clarify whether the erosion of the world&39;s most vulnerable ice sheets, in Greenland and west Antarctica, can continue to accelerate. The effort involves field and satellite analyses and sifting for clues from past warm periods.
Things are definitely far more serious than anyone would have thought five years ago.

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Unlike other forms of narrative art, a play, to be successful , must give pleasure to its

A. plays written for Restoration audiences do not appeal to modern audiences.
B. plays are superior to novels as a form. of narrative art.
C. Restoration audiences were representative of the whole population of their time.
D. playgoers and novel readers are typically distinct and exclusive groups.
E. Restoration drama achieved popular success at the expense of critical success.

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21 . The program to control the entry of illegal drugs into the country was a failure in 19If the program had been successful, the wholesale price of most illegal drugs would not have dropped substantially in 19The argument in the passage depends on which of the following assumptions？

A. The supply of illegal drugs dropped substantially in 1987.
B. The price paid for most illegal drugs by the average consumer did not drop substantially in 1987.
C. Domestic production of illegal drugs increased at a higher rate than did the entry of such drugs into the country.
D. The wholesale price of a few illegal drugs increased substantially in 1987.
E. A drop in demand for most illegal drugs in 1987 was not the sole cause of the drop in their wholesale price.

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From a certain farming region, trucks can carry vegetables to market in New Mexico in two

A. Vegetables can be sold more profitably when shipped by train than by truck.
B. Other than speed and cost, there are no significant differences between truck and train transportation from the farming region to New Mexico.
C. The time required to ship vegetables by train from the farming region to New Mexico could be reduced to two days if the price for this service were raised.
D. Most owners of vegetables in the region are more concerned with shipping costs than with the time involved in shipping vegetables to market.
E. Transportation of vegetables by truck is worth at least $ 200 per day to owners of the vegetables in the farming region.

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Popular culture in the United States has become Europeanized to an extent unimaginable twenty-five years ago. Not many people then drank wine with meals, and no one drank imported mineral water. No idea would have been more astonishing than that Americans would pay to watch soccer games. Such thoughts arise because of a report that the American Association of State Highway and Transportation Officials has just adopted a proposal to develop the countrys first comprehensive interstate system of routes for bicycles. Which of the following inferences is best supported by the passage？

A. Long-distance bicycle routes are used in Europe.
B. Drinking imported mineral water is a greater luxury than drinking imported wine.
C. United States culture has benefited from exposure to foreign ideas.
D. Most Europeans make regular use of bicycles.
E. The influence of the United States on European culture has assumed unprecedented proportions in the last twenty-five years.

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