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How many years will it be before the world runs out of oil The question is far from an academic exercise. This year oil hit a near record high of $40 a barrel, and Royal Dutch/Shell Group downgraded its reserves by 4.5 billion barrels.
While consumers pay for perceived shortages at the pump, scientists and economists struggle to reach consensus over "proven oil reserves," or how much oil you can realistically mine before recovery costs outstrip profits. Economist Leonardo Maugeri fired up the debate that accused the "oil doomsters" of crying wolf.
Oil pessimists estimate that maximum oil production around the globe will peak in 2008 as demand rises from developing economies such as China. "If you squeezed all the oil in Iraq into a single bottle, you could fill four glasses, with the world consuming one glass of oil each year," says a physicist. "We’ve consumed nine bottles since oil was discovered, and we have another 9 or 10 in the refrigerator. How many more are there Some say five or six, but we say three."
Others believe, like Maugeri, that the number of glasses is virtually limitless. John Felmy, chief economist at the American Petroleum Institute, argues that peak oil-production estimates are so far off that. "Ever since oil was first harvested in the 1800s, people have said we’d run out of the stuff," Felmy says. In the 1880s a Standard Oil executive sold off shares in the company out of fear that its reserves were close to drying up. Some scientists said in the 1970s that we’d hit peak oil in 2003. It didn’t happen.
If there is an end to the debate, advanced oil-recovery technologies will most likely find it. A new seismic survey technique, for instance, sends sound waves of varying frequencies thousands of meters belowground. Microphones arrayed aboveground record the reflected signals, and computer software models a 3-D portrait of possible oil hot spots. The surveys have now added a fourth dimension, creating a time-lapse simulation of fluid movements.
Companies are also finding sophisticated ways to mine more oil from existing wells. Flexible, coiled-tube drills that carve out horizontal side paths are a marked improvement over conventional, rigid drills that move only straight down. Using such technology, companies hope to soon harvest 50 to 60 percent of oil from existing wells, up from today’s 35 percent.
Biotechnology, too is keeping the black gold flowing. University of Albert scientists are searching for microorganisms that could dilute viscous, hard-to-recover oil and make it flow more freely.
"Technology can help push peak oil production further and further out," says an expert. But only time will tell when oil production will peak.
Advanced technologies can do all of the following EXCEPT that ______.

A. they can find oil deeper in the ground
B. they can increase mining efficiency
C. they can cultivate microorganisms that produce oil
D. they can delay peak oil production

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From Para. 4 we know that______. A. the author thinks life is easy. B. the author regards the boy as a looser. C. the author wants to comfort the boy. D. the author encourages the boy with a warm heart.

As I sit at my desk and observe the frenzied play of these children who are working so hard at being children, I see a small boy to my right. What catches my eye is that he is standing in the area of the soccer goal, by himself, looking down at his shoes. He picks at his navy blue sweat jacket, pulling the string ties back and forth through the casing. He stubs his Nike’d tennis shoe in the dirt, again, and again, and again. I see his lips move--he seems to be talking to himself, all alone, oblivious to the world around him. There are children at play in the background, plenty to team up with, yet he stands idle, off to himself.
Watching him, I begin to fantasize about his melancholy. Is he an only child of working parents who are so busy with their own lives they don’t have time for him Or is he one of several children, caught in the stampede of family life, getting trampled on by the older children as they pass him up, and pulled down by the younger siblings as they compete with him. Is he loved or abused Smart or slow to learn What does he think about when he’s by himself What are his dreams His fears Is he a new child, too shy to make friends Or is he a victim of the cruelties of child’s play
Days of my own childhood come flooding back to me. Remembering the days when I felt as he must be feeling now, so alone. As an adult, I can still feel that sometime hollowness. I understand these feelings even less than I did when I was his age. I ache for this small child that bas so much to learn and experience, as much potential for pain in his future as happiness. I want to reach out to him, wrap my arms around him and tell him that it’s ok, he’s not alone, that I care, as will so many others in his life to come. I want to assure him that it’s alright to feel the way he does, but that it gets better and he must look to the good things, to learn from his experiences. I want to give him all the answers to all the questions that no one ever gets until they don’t need to know anymore.
I find myself rising from behind my desk, mesmerized by the little form before me. I walk towards the window, my eyes not budging front their goal. He’s still plowing the earth with the toe of his shoe, talking away to whatever has a moment to listen. My eyes fill with tears--I can’t bear this pain any more. I reach out for the window frame, leaning into it in weariness of a life hard fought, knowing of the battle he has yet to face...

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Which of the following would NOT cause a sea cucumber to release its internal organs into the water A. A touch. B. Food. C. Unusually warm water D. Pollution.

Although they have voracious appetites, eating day and night, sea cucumbers have the capacity to become quiescent and live at a low metabolic rate-feeding sparingly or not at all for long periods, so that the marine organisms that provide their food have a chance to multiply. If it were not for this faculty, they would devour all the food available in a short time and would probably starve themselves out of existence.
But the most spectacular thing about the sea cucumber is the way it defends itself. Its major enemies are fish and crabs, when attacked, it squirts all its internal organs into water. It also casts off attached structures such as tentacles. The sea cucumber will eviscerate and regenerate itself if it is attacked or even touched l it will do the same if the surrounding water temperature is too high or if the water becomes too polluted.