GRE Exam Dumps : GRE General Test

Exhibit.

The variance of n numerical data x1, x2, x3, , , , , xn with the mean x is equal to were S is the sum of the equal differences for

For the shares of stock purchased and then sold by the investors shown, the mean of the 5 numbers for Stock Y is 50 and the corresponding mean for Stock X is 70. The variance of the 5 numbers for Stock }' is what fraction of the corresponding variance for Stock X ?

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As originally formulated, the selfish-herd theory of prey species aggregation assumed that predatory attacks were equally likely to be launched from any position within the environment. In some circumstances (e.g.. avian predators attacking prey from above), such an approach is appropriate. However, as James et at. argue, in many predator-prey associations, attacks are unlikely to occur from positions within the group. For example, it is likely that an ambushing predator waiting in the path of a group would be detected before the group moves over its position. Hence, in many ecological situations, predatory attacks on grouped prey will occur exclusively from outside the group. In such circumstances, there is a strong premium to a group member in being in the interior of the group.

The passage suggests that compared to members of the prey groups in "some circumstances." certain members of the prey groups in "many ecological situations" are likely to be less

Sensationalism—the purveyance of emotionally charged content. focused mainly on violent crime, to a broad public—has often been decried, but the full history of the phenomenon has yet to be written. Scholars have tended to dismiss sensationalism as unworthy of serious study, based on two pervasive though somewhat incompatible assumptions: first, that sensationalism is essentially a commercial product, built on the exploitation of modern mass media, and second, that it appeals almost entirely to a simple, basic emotion and thus has tittle history apart from the changing technological means of spreading it. An exploration of sensationalism's early history, however, challenges both assumptions and suggests that they have tended to obscure the complexity and historicity of the genre.

According to the passage, scholars have not given sensationalism serious consideration because they believe sensationalism