Most worthwhile careers require some kind of specialized training. Ideally, therefore, the choice of an 1 should be made even before choice of a curriculum in high school. Actually, 2 , most people make several job choices during their working lives, 3 because of economic and industrial changes and partly to improve 4 position. The "one perfect job" does not exist. Young people should 5 enter into a broad flexible training program that will 6 them for a field of work rather than for a single 7 .Unfortunately many young people have to make career plans 8 benefit of help from a competent vocational counselor or psychologist. Knowing 9 about the occupational world, or themselves for that matter, they choose their lifework on a hit-or-miss 10 . Some drift from job to job. Others 11 to work in which they are unhappy and for which they are not fitted.One common mistake is choosing an occupation for 12 real or imagined prestige. Too many high-school students—or their parents for them—choose the professional field, 13 both the relatively small proportion of workers in the professions and the extremely high educational and personal 14 . The imagined or real prestige of a profession or a "white-collar" job is 15 good reason for choosing it as life"s work. 16 , these occupations are not always well paid. Since a large proportion of jobs are in mechanical and manual work, the 17 of young people should give serious 18 to these fields.Before making an occupational choice, a person should have a general idea of what he wants 19 life and how hard he is willing to work to get it. Some want security; others are willing to take 20 for financial gain. Each occupational choice has its demands as well as its rewards.
A. Therefore
B. However
C. Nevertheless
D. Moreover
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During the nineteen years of his career, France Battiate has won the ______ of a wide audience outside Italy.
A. enjoyment
B. appreciation
C. evaluation
D. reputation
The energy contained in rock within the earth"s crust represents a nearly unlimited energy source, but until recently commercial retrieval has been limited to underground hot water and/or steam recovery systems. These systems have been developed in areas of recent volcanic activity, where high rates of heat flow cause visible eruption of water in the form of geysers and hot springs. In other areas, however, hot rock also exists near the surface but there is insufficient water present to produce eruptive phenomena. Thus a potential hot dry rock (HDR) reservoir exists whenever the amount of spontaneously produced geothermal fluid has been judged inadequate for existing commercial systems.As a result of recent energy crisis, new concepts for creating HDR recovery systems—which involve drilling holes and connecting them to artificial reservoirs placed deep within the crest—are being developed. In all attempts to retrieve energy from HDRs, artificial stimulation will be required to create either sufficient permeability or bounded flow paths to facilitate the removal of heat by circulation of a fluid over the surface of the rock.The HDR resource base is generally defined to include crustal rock that is hotter than 150℃, is at depths less than ten kilometers, and can be drilled with presently available equipment. Although wells deeper than ten kilometers are technically feasible, prevailing economic factors will obviously determine the commercial feasibility of wells at such depths. Rock temperatures as low as 100℃ may be useful for space heating; however, for producing electricity, temperatures greater than 200℃ are desirable. The geothermal gradient, which specifically determines the depth of drilling required to reach a desired temperature, is a major factor in the recoverability of geothermal resources. Temperature gradient maps generated from oil and gas well temperature-depth records kept by the American Association of Petroleum Geologists suggest that tappable high-temperature gradients are distributed all across the United States. (There are many areas, however, for which no temperature gradient records exist.)Indications are that the HDR resource base is very large. If an average geothermal temperature gradient of 22℃ per kilometer of depth is used, a staggering 13,000,000 quadrillion B.T.U. "s of total energy are calculated to be contained in crustal rock to a ten-kilometer depth in the United States. If we conservatively estimate that only about 0.2 percent is recoverable, we find a total of all the coal remaining in the United States. The remaining problem is to balance the economics of deeper, hotter, more costly wells and shallower, cooler, less expensive wells against the value of the final product, electricity and/or heat. Which of the following would be the most appropriate title for the passage
A. Energy from Water Sources: The Feasibility of Commercial Systems
B. Geothermal Energy Retrieval: Volcanic Activity and Hot Dry Rocks
C. Energy Underground: Geothermal Sources Give Way to Fossil Fuels
D. Tappable Energy for America"s Future: Hot Dry Rocks
The energy contained in rock within the earth"s crust represents a nearly unlimited energy source, but until recently commercial retrieval has been limited to underground hot water and/or steam recovery systems. These systems have been developed in areas of recent volcanic activity, where high rates of heat flow cause visible eruption of water in the form of geysers and hot springs. In other areas, however, hot rock also exists near the surface but there is insufficient water present to produce eruptive phenomena. Thus a potential hot dry rock (HDR) reservoir exists whenever the amount of spontaneously produced geothermal fluid has been judged inadequate for existing commercial systems.As a result of recent energy crisis, new concepts for creating HDR recovery systems—which involve drilling holes and connecting them to artificial reservoirs placed deep within the crest—are being developed. In all attempts to retrieve energy from HDRs, artificial stimulation will be required to create either sufficient permeability or bounded flow paths to facilitate the removal of heat by circulation of a fluid over the surface of the rock.The HDR resource base is generally defined to include crustal rock that is hotter than 150℃, is at depths less than ten kilometers, and can be drilled with presently available equipment. Although wells deeper than ten kilometers are technically feasible, prevailing economic factors will obviously determine the commercial feasibility of wells at such depths. Rock temperatures as low as 100℃ may be useful for space heating; however, for producing electricity, temperatures greater than 200℃ are desirable. The geothermal gradient, which specifically determines the depth of drilling required to reach a desired temperature, is a major factor in the recoverability of geothermal resources. Temperature gradient maps generated from oil and gas well temperature-depth records kept by the American Association of Petroleum Geologists suggest that tappable high-temperature gradients are distributed all across the United States. (There are many areas, however, for which no temperature gradient records exist.)Indications are that the HDR resource base is very large. If an average geothermal temperature gradient of 22℃ per kilometer of depth is used, a staggering 13,000,000 quadrillion B.T.U. "s of total energy are calculated to be contained in crustal rock to a ten-kilometer depth in the United States. If we conservatively estimate that only about 0.2 percent is recoverable, we find a total of all the coal remaining in the United States. The remaining problem is to balance the economics of deeper, hotter, more costly wells and shallower, cooler, less expensive wells against the value of the final product, electricity and/or heat. According the passage, an average geothermal gradient of 22℃ per kilometer of depth can be used to ______.
A. balance the economics of HDR energy retrieval against that of underground hot water or steam recovery systems
B. determine the amount of energy that will be used for space heating in the United States
C. provide comparisons between hot water and HDR energy sources in United States
D. estimate the total HDR resource base in the United States
The energy contained in rock within the earth"s crust represents a nearly unlimited energy source, but until recently commercial retrieval has been limited to underground hot water and/or steam recovery systems. These systems have been developed in areas of recent volcanic activity, where high rates of heat flow cause visible eruption of water in the form of geysers and hot springs. In other areas, however, hot rock also exists near the surface but there is insufficient water present to produce eruptive phenomena. Thus a potential hot dry rock (HDR) reservoir exists whenever the amount of spontaneously produced geothermal fluid has been judged inadequate for existing commercial systems.As a result of recent energy crisis, new concepts for creating HDR recovery systems—which involve drilling holes and connecting them to artificial reservoirs placed deep within the crest—are being developed. In all attempts to retrieve energy from HDRs, artificial stimulation will be required to create either sufficient permeability or bounded flow paths to facilitate the removal of heat by circulation of a fluid over the surface of the rock.The HDR resource base is generally defined to include crustal rock that is hotter than 150℃, is at depths less than ten kilometers, and can be drilled with presently available equipment. Although wells deeper than ten kilometers are technically feasible, prevailing economic factors will obviously determine the commercial feasibility of wells at such depths. Rock temperatures as low as 100℃ may be useful for space heating; however, for producing electricity, temperatures greater than 200℃ are desirable. The geothermal gradient, which specifically determines the depth of drilling required to reach a desired temperature, is a major factor in the recoverability of geothermal resources. Temperature gradient maps generated from oil and gas well temperature-depth records kept by the American Association of Petroleum Geologists suggest that tappable high-temperature gradients are distributed all across the United States. (There are many areas, however, for which no temperature gradient records exist.)Indications are that the HDR resource base is very large. If an average geothermal temperature gradient of 22℃ per kilometer of depth is used, a staggering 13,000,000 quadrillion B.T.U. "s of total energy are calculated to be contained in crustal rock to a ten-kilometer depth in the United States. If we conservatively estimate that only about 0.2 percent is recoverable, we find a total of all the coal remaining in the United States. The remaining problem is to balance the economics of deeper, hotter, more costly wells and shallower, cooler, less expensive wells against the value of the final product, electricity and/or heat. It can be inferred from the passage that the availability of temperature-depth records for any specific area in the United States depends primarily on the ______.
A. possibility that HDRs may be found in that area
B. existence of previous attempts to obtain oil or gas in that area
C. history of successful hot water or steam recovery efforts in that area
D. failure of inhabitants to conserve oil gas reserves in that area