2016年6月大学英语四级考试模拟题及答案(10)

　　Barges and steamers carried the iron ore through Lake Superior to depots on the southern shores of Lake Michigan and Lake Erie. With dizzying speed Gary, Indiana, and Toledo, Youngstown, and Cleveland, Ohio, became major steelmanufacturing centers. Pittsburgh was the greatest steel city of all.

　　Steel was the basic building material of the industrial age. Production skyrocketed from seventyseven thousand tons in 1870 to over eleven million tons in 1900.

　　31.According to the passage, the railroad industry preferred steel to iron because steel was ____.

　　A.cheaper and more plentiful

　　B.lighter and easier to mold

　　C.cleaner and easier to mine

　　D.stronger and more durable

　　32.According to the passage, how did Bessemer method make the mass production of steel possible?

　　A.It directed air at melted iron in a furnace, removing all impurities.

　　B.It slowly heated iron ore then stirred it and heated it again.

　　C.It changed iron ore into iron which was a substitute for steel.

　　D.It could quickly find deposits of iron ore under the ground.

　　33.According to the passage, where were large deposits of iron uncovered?

　　A.In Pittsburgh. B.In the Mesabi Range.

　　C.Near Lake Michigan.D.Near Lake Erie.

　　34.The words “Barges and steamers” could best be replaced by which of the following?

　　A.Trains.B.Planes.C.Boats.D.Trucks.

　　35.It can be inferred from the passage that the mass production of steel caused ____.

　　A.a decline in the railroad industry

　　B.a revolution in the industrial world

　　C.an increase in the price of steel

　　D.a feeling of discontent among steel workers

　　Questions 36 to 40 are based on the following passage:

　　There were two widely divergent influences on the early development of statistical methods. Statistics had a mother who was dedicated to keeping orderly records of governmental units (state and statistics come from the same Latin root, status) and a gentlemanly gambling father who relied on mathematics to increase his skill at playing the odds in games of chance. The influence of the mother on the offspring, statistics, is represented by counting, measuring, describing, tabulating, ordering, and the taking of censuses—all of which led to modern descriptive statistics. From the influence of the father came modern inferential statistics, which is based squarely on theories of probability.

　　Descripitive statistics involves tabulating, depicting, and describing collections of data. These data may be either quantitative, such as measures of height, intelligence, or grand level—variables that are characterized by an underlying continuum—or the data may represent qualitative variables, such as sex, college major, or personality type. Large masses of data must generally undergo a process of summarization or reduction before they are comprehensible. Descriptive statistics is a tool for describing or summarizing or reducing to comprehensible from the properties of an otherwise unwieldy mass of data.

　　Inferential statistics is a formalized body of methods for solving another class of problems that present great difficulties for the unaided human mind. This　general class of problems characteristically involves attempts to make prediction using a sample of observations. For example, a school superintendent wishes　to determine of the proportion of children in a large school system who come to school without breakfast, have been vaccinated for flu, or whatever. Having a little knowledge of statistics, the superintendent would know that it is unnecessary　and inefficient to question each child; the proportion for the entire district could be estimated fairly accurately from a sample of as few as 100 children. Thus, the purpose of inferential statistics is to predict or estimate characteristics of a population from a knowledge of the characteristics of only a sample of the population.