更多"A. Get some small change. B. Find "的相关试题:
[单项选择]Passage Three
Some desert regions get no rainfall for months, and even years. Yet water can be found if you dig deep enough. For a long time this was a puzzling question. Then geologists found the answer. The underground water is rainwater--but the rain fell hundreds of miles away! It soaked into the ground and then flowed underground through a rock sandwich.
A rock sandwich with water in the filling has a scientific name: aquifer. An aquifer is composed of two or more layers of nonporous rock. That’s the bread of the sandwich. The filling is a layer of porous rock or sand. The whole sandwich, or aquifer, is titled at a slant. The higher end is in a region of good rainfall, where the rain soaks into the porous rock or sand. The rainwater flows down at a slant between the nonporous rock layers. If a well is drilled through the top layer, the water flows up into the well.
If the upper end of the aquifer is higher than the top of the well, the water is forc
A. weather patterns
B. boundaries and land claims
C. the surface layers of the earth
D. the orbits of heavenly bodies
[填空题]Although some students can get merit money from colleges or universities, still no one has ever got the amount of money Large enough to cover the tuition.
[单项选择]Some oil companies plan to get rid of some of the pollution they produce by pumping it into rocks deep inside the Earth, where they say it will stay for thousands of years. Other people, though, aren’t so sure this is advisable; environmental groups say that putting this pollution back into the Earth is a bad idea.
When oil burns, it doesn’t just produce heat: it also produces carbon dioxide. Carbon dioxide is a natural part of the air, but because people burn so much oil, there’s too much carbon dioxide in the air. This extra carbon dioxide is pollution; some scientific studies show that carbon dioxide is one of the "greenhouse gases ’that is causing the Earth’s temperature to rise.
Environmentalists say that the oil companies’ plans may not work. The oil companies say they are making sure that the gas will never escape, but environmentalists wonder how the oil companies can be so sure that the gas won’ t seep into the air. They also point out that there’s no way to check to
A. are further polluting the air by using more oil than clean energy.
B. are not really concerned with solving the problem of pollution.
C. are attempting to reduce the pollution they have done to the air.
D. are in need of research and equipment in pollution prevention.
