Hoping to alleviate some of the financial burdens of a growing population, property taxes last year were raised by an eleven percent increase by the county government.

In the years following an eight-cent increase in the federal tax on a pack of cigarettes, sales of cigarettes fell ten percent. In contrast, in the year prior to the tax increase, sales had fallen one percent. The volume of cigarette sales is therefore strongly related to the after-tax price of a pack of cigarettes.

The argument above requires which of the following assumptions?

In response to viral infection, the immune systems of mice typically produce antibodies that destroy the virus by binding to proteins on its surface. Mice infected with a herpesvirus generally develop keratitis, a degenerative disease affecting part of the eye. Since proteins on the surface of cells in this part of the eye closely resemble those on the herpesvirus surface, scientists hypothesize that these cases of keratitis are caused by antibodies to herpesvirus.

Which of the following, if true, gives the greatest additional support to the scientists' hypothesis?

Scientists typically do their most creative work before the age of forty. It is commonly thought that this happens because aging by itself brings about a loss of creative capacity. However, a study has found that almost all scientists who produce highly creative work beyond the age of forty entered their fields late and less than a dozen years before their creative breakthroughs. Since creative breakthroughs by scientists under forty also generally occur within a dozen years of the scientist's entry into the field, the study's finding strongly suggests that the real reason why scientists over forty rarely produce highly creative work is not due to age but rather because most have spent too long in their fields.

In the argument given, the two portions in boldface play which of the following roles?

Lyme disease is caused by a bacterium transmitted to humans by deer ticks. Generally deer ticks pick up the bacterium while in the larval stage from feeding on infected white-footed mice. However, certain other species on which the larvae feed do not harbor the bacterium. Therefore, if the population of these other species were increased, the number of ticks acquiring the bacterium and hence the number of people contracting Lyme disease-would likely decline.

Which of the following, if true, most strengthens the argument?

The percentage of households with an annual income of more than $40,000 is higher in Merton county than in any other county. However, the percentage of households with an annual income of $60,000 or more is highest in Sommer county.

If the statements above are true, which of the following can properly be concluded on the basis of them?

Ecologist: The Scottish Highlands were once the site of extensive forests, but these forests have mostly disappeared and been replaced by peat bogs. The common view is that the Highlands' deforestation was caused by human activity, especially agriculture. However, agriculture began in the Highlands less than 2,000 years ago. Peat bogs, which consist of compressed decayed vegetable matter, build up by only about one foot per 1,000 years and, throughout the Highlands, remains of trees in peat bogs are almost all at depths great than four feet. Since climate changes that occurred between 7,000 and 4,000 years ago favored the development of peat bogs rather than the survival of forests, the deforestation was more likely the result of natural processes than of human activity.

In the ecologist's argument the two portions in boldface play which of the following roles?

According to the passage, which of the following is true of the average rate at which real GDP per capita grew in the twenty-four years immediately before 1997?

It can be inferred from the passage that which of the following is the reason that the author faults the journalists referred to in highlight text?

The primary purpose of the passage is to

According to the passage, which of the following is the reason why short-term price promotions do not attract new long-term customers to a brand?

The passage suggests that evidence for price promotions' "effect on the bottom line" (with yellow highlight) is provided by

Driving the steep road to the mountaintop Inca ruins of Machu Picchu is potentially dangerous and hiking there is difficult. Now the Peruvian government is installing a cable car that will make access much easier, and hence result in a large increase in tourism. However, since the presence of large numbers of tourists tends to accelerate the deterioration of a site, installation of the cable car is certain to result in harm to the ruins.

Which of the following, if true, most seriously calls into question the argument?