As of the late 1980’s, neither theorists nor large-scale computer climate models could accurately predict whether cloud systems would help or hurt a warming globe. Some studies suggested that a four percent increase in stratocumulus clouds over the ocean could compensate for a doubling in atmospheric carbon dioxide, preventing a potentially disastrous planetwide temperature increase. On the other hand, an increase in cirrus clouds could increase global warming.
That clouds represented the weakest element in climate models was illustrated by a study of fourteen such models. Comparing climate forecasts for a world with double the current amount of carbon dioxide, researchers found that the models agreed quite well if clouds were not included. But when clouds were incorporated, a wide range of forecasts was produced. With such discrepancies plaguing the models, scientists could not easily predict how quickly the world’s climate would change, nor could they tell which regions would face dustier droughts or deadlier monsoons.
24. The author of the passage is primarily concerned with
(A) confirming a theory
(B) supporting a statement
(C) presenting new information
(D) predicting future discoveries
(E) reconciling discrepant findings
25. It can be inferred that one reason the fourteen models described in the passage failed to agree was that
(A) they failed to incorporate the most up-to-date information about the effect of clouds on climate
(B) they were based on faulty information about factors other than clouds that affect climate
(C) they were based on different assumptions about the overall effects of clouds on climate
(D) their originators disagreed about the kinds of forecasts the models should provide
(E) their originators disagreed about the factors other than clouds that should be included in the models
26. It can be inferred that the primary purpose of the models included in the study discussed in the second paragraph
of the passage was to
(A) predict future changes in the world’s climate
(B) predict the effects of cloud systems on the world’s climate
(C) find a way to prevent a disastrous planetwide temperature increase
(D) assess the percentage of the Earth’s surface covered by cloud systems
(E) estimate by how much the amount of carbon dioxide in the Earth’s atmosphere will increase
27. The information in the passage suggests that scientists would have to answer which of the following questions in order to predict the effect of clouds on the warming of the globe?
(A) What kinds of cloud systems will form over the Earth?
(B) How can cloud systems be encouraged to form over the ocean?
(C) What are the causes of the projected planetwide temperature increase?
(D) What proportion of cloud systems are currently composed of cirrus of clouds?
(E) What proportion of the clouds in the atmosphere form over land masses?===========RC2=====================Although the development of new infrastructure (such public facilities
as power plants, schools, and bridges) is usually determined
(3)by governmental planning,
sometimes this development can be planned more flexibly
and realistically by private investors who anticipate profit from the
collection of user fees. Such profits can contribute to the financing
of more infrastructure if demand proves great enough, whereas the
reluctance of developers to invest in such projects can signal that
additional infrastructure is not needed. During the
economic boom of the 1980’s, for example, the state
of Virginia authorized private developers
(12) to build a $300 million toll road. These developers obtained the needed
right-of-way from property owners, but by 1993 they still had not raised the necessary financing.
The unwillingness of investors to finance this project does not negate the viability of privately financed roads; rather, it illustrates a virtue of private financing. If a road appears unlikely to attract enough future traffic to pay for the road, then it should not be built.
24. The primary purpose of the passage is to
(A) build a case for increasing the development of new infrastructure
(B) advocate an alternative to government financing of infrastructure
(C) explain the failure of a privately financed venture
(D) suggest the types of infrastructure most appropriate for private financing
(E) argue against government restrictions on developing new infrastructure
25. The passage implies that the “governmental planning” mentioned in line 3 may lead to which of the following problems?
(A) Improper use of profits derived from user fees
(B) Unduly slow development of necessary new infrastructure
(C) Unrealistic decisions about developing new infrastructure
(D) Incorrect predictions about profits to be gained from user fees
(E) Obstruction of private financing for the development of new infrastructure
26. According to the passage, which of the following is true of the toll road mentioned in line 12?
(A) After it was built, it attracted too little traffic to pay for its construction.
(B) It was partially financed by the state of Virginia.
(C) Its development was authorized during an economic boom.
(D) Its construction was controversial among local residents.
(E) Its developers were discouraged by governmental restrictions on acquiring the necessary land.
27. The passage suggests that which of the following would occur if a privately financed bridge that proved to be profitable failed after a number of years to meet the demands of traffic?
(A) Private developers who financed the bridge would rely on governmental authorities to develop new infrastructure.
(B) User fees would be increased so that usage would become more costly.
(C) Governmental authorities would be reluctant to rely on private contractors to develop a new bridge.
(D) The success of the project would be jeopardized by public dissatisfaction with the project’s adequacy.
(E) Profits generated by user fees would be used to help finance the construction of new infrastructure to alleviate the traffic problem.