33.Why are the photographs mentioned in line 16referred to as an "experiment"?

(A)The photographs were not very clear.

(B)The purpose of the photographs was to explain the process.

(C)The photographer used inferior equipment

(D)The photographer thought the cat might be injured.

34.Which of the following can be inferred about high-speed photography in the late 1800's?

(A)It was a relatively new technology.

(B)The necessary equipment was easy to obtain.

(C)The resulting photographs are difficult to interpret.

(D)It was not fast enough to provide new information.

35.The word "rotates"in line 19is closest in meaning to

(A)drops

(B)turns

(C)controls

(D)touches

36.According to the passage,a cat is able to right itself in midair because it is

(A)frightened

(B)small

(C)intelligent

(D)flexible

37.The word "readily"in line 24is closest in meaning to

(A)only

(B)easily

(C)slowly

(D)certainly

38.How did scientists increase "the speed of their perceptions a thousandfold"(lines 25-26)?

(A)By analyzing photographs

(B)By observing a white cat in a dark room

(C)By dropping a cat from a greater height.

(D)By studying Newton's laws of motion.

Question 39-50

The changing profile of a city in the United States is apparent in the shifting definitions used by the United States Bureau of the Census.In 1870the census officially distinguished the nation's "urban"from its "rural"population for the first time."Urban population"was defined as persons living in towns of 8,000inhabitants or more.But after 1900it meant persons living in incorporated places having 2,500or more inhabitants.

Then,in 1950the Census Bureau radically changed its definition of "urban"to take account of the new vagueness of city boundaries.In addition to persons living in incorporated units of 2,500or more,the census now included those who lived in unincorporated units of that size,and also all persons living in the densely settled urban fringe,including both incorporated and unincorporated areas located around cities of 50,000inhabitants or more.Each such unit,conceived as an integrated economic and social unit with a large population nucleus,was named a Standard Metropolitan Statistical Area (SMSA).

Each SMSA would contain at least (a)one central city with 50,000inhabitants or more or (b)two cities having shared boundaries and constituting,for general economic and social purposes,a single community with a combined population of at least 50,000,the smaller of which must have a population of at least 15,000.Such an area included the county in which the central city is located,and adjacent counties that are found to be metropolitan in character and economically and socially integrated with the country of the central city.By 1970,about two-thirds of the population of the United States was living in these urbanized areas,and of that figure more than half were living outside the central cities.

While the Census Bureau and the United States government used the term SMSA (by 1969there were 233of them),social scientists were also using new terms to describe the elusive,vaguely defined areas reaching out from what used to be simple "town"and "cities".A host of terms came into use:"metropolitan regions","polynucleated population groups","conurbations","metropolitan clusters","megalopolises",and so on.