In 2005, 80% of the Central City School Districts total expenditures came from local property taxes, and the rest came from the state government`s Aid to Schools Program. If the state had reduced its aid to the district by 50%, by what percentage would local property taxes have had to be increased in order for the district to maintain the same level of expenditures?
The revenue from lottery ticket sales is divided between prize money and the various uses shown in the graph labeled "Proceeds." In 2009, what percent of the money spent on tickets was returned to the purchasers in the form of prize money?
In how many years from 2001 through 2008, inclusive, did the sales of ABC Mega Stores exceed the average of the annual sales during that period?
In which of the following pairs of years were the ratios of Republican receipts to Democratic receipts most nearly equal?
We now know that what constitutes practically all matter is empty space; relatively enormous voids in which revolve with lightening velocity infinitesimal particles so utterly small that they have never been seen or photographed. The existence of these particles has been demonstrated by mathematical physicists and their operations determined by ingenious laboratory experiments. It was not until 1911 that experiments by Sir Ernest Rutherford revealed the architecture of the mysterious atom. Moseley, Bohr, Fermi, Milliken, Compton, Urey, and others have also worked on the problem.

Matter is composed of molecules whose average diameter is about 1/125 millionth of an inch. Molecules are composed of atoms so small that about 5 million could be placed in a row on the period at the end of this sentence. Long thought to be the ultimate, indivisible constituent of matter, the atom has been found to consist roughly of a proton, the positive electrical element in the atomic nucleus, surrounded by electrons, the negative electric elements swirling about the proton.
According to the passage, all of the following were true of the center of an atom EXCEPT that it
Given the context of social change in the early 1960s, black history was now the object of unprecedented attention among wide segments of the American population, black and white. In academe nothing demonstrated this growing legitimacy of black history better than the way in which certain scholars of both races, who had previously been ambivalent about being identified as specialists in the field, now reversed themselves.

Thus Frenise Logan, returning to an academic career, decided to attempt to publish his doctoral dissertation on blacks in late nineteenth-century North Carolina. A 1960 award encouraged him to do further research, and his expanded The Negro in North Carolina, 1876–1894 appeared in 1964. It is true that as late as 1963 a white professor advised John W. Blassingame to avoid black history if he wanted to have "a future in the historical profession." Yet more indicative of how things were going was that 1964–1965 marked a turning point for two of Kenneth Stampp`s former students-Nathan Huggins and Leon Litwack. The changing intellectual milieu seems to have permitted Huggins, whose original intention of specializing in African and Afro-American history had been overruled by practical concerns, to move into what became his long-range commitment to the field. By 1965 when his interest in intellectual history found expression in the idea of doing a book on the Harlem Renaissance, the factors that earlier would have discouraged him from such a study had dissipated. For Litwack the return to black history was an especially vivid experience, and he recalls the day he spoke at the University of Rochester, lecturing on Jacksonian democracy. Some students in the audience, sensing that his heart was just not in that topic, urged him to undertake research once again in the field to which he had already contributed so significantly. He settled on the study that became Been in the Storm So Long (1979). In short, both Huggins and Litwack now felt able to dismiss the professional considerations that had loomed so large in their earlier decision to work in other specialties and to identify themselves with what had hitherto been a marginal field of inquiry.
Throughout the passage the author seeks to support his point primarily by the use of
Statistics indicate that, on the average, women executives` salaries are about 20% lower than the salaries of men in comparable jobs. This is true despite the job discrimination suits filed in the 1970`s by the federal government against firms such as A.T. & T. and the Bank of America, as well as despite the passage of laws forbidding job discrimination by gender in many states and localities. In the face of this unrelenting prejudice against women, it is manifest that only an amendment to the U.S. Constitution can fully remedy the iniquities under which today`s women are laboring.
All of the following are weaknesses of the above argument EXCEPT that
In the days of sailing ships, fresh food was unavailable on board, and at the end of long voyages many sailors would contract scurvy, a potentially life-threatening condition. Today we recognize ascorbic acid as a cure for this condition, but in the late seventeenth and early eighteenth century medical practitioners and scientists had no such surety. Shakespeare`s son-in-law, the seventeenth-century herbalist and surgeon John Hall, cured several cases of scurvy by administering an acidic brew composed of brooklime, scurvy grass and watercress, all herbs rich in ascorbic acid. The celebrated physician William Harvey suggested that sailors take lemon juice to ward off scurvy; he hypothesized that citric acid, the specific acid in lemon juice, would prevent the disease. In the mid-eighteenth century, the Scottish naval surgeon James Lind conducted an experiment involving 12 sick sailors to discover whether the acid was responsible for the cure. All of the sailors received the same diet except that in addition each day two of the men were given small amounts of dilute sulfuric acid, two others some spoonfuls of vinegar (acetic acid), two more a quart of cider, two more half a pint of seawater, two more a paste of spices with some barley water, and the remaining two a lemon and two oranges. Only those given the lemon and oranges recovered from the disease.
The hypothesis tested by Lind was that


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