17. Which of the following statements best expresses the irony pointed out by the authors in lines 13-16 of the passage?
(A) Female delinquents tend to commit victimless crimes more frequently than their male counterparts.
(B) The predicament of male delinquents receives more attention than that of females because males are accused of more serious crimes.
(C) Adults are frequently punished less severely than adolescents for committing more serious crimes.
(D) The juvenile justice system cannot correct its biases because it does not even recognize them.
(E) Although the number of female delinquents is steadily increasing, the crimes of which they are accused are not particularly serious.
18. It can be inferred from the passage that the authors believe traditional stereotypes of women to be
(A) frequently challenged
(B) persistently inexplicable
(C) potentially harmful
(D) rapidly changing
(E) habitually disregarded
19. The passage suggests that scholars in criminal justice could be criticized for which of the following?
(A) Underestimating the seriousness of juvenile crime
(B) Rationalizing the distinction made between juveniles and adults in the legal system
(C) Concerning themselves too little with the prevention of juvenile delinquency
(D) Focusing on those whose crimes have involved damage to persons or property
(E) Failing to point out injustices in the correctional system
Scattered around the globe are more than one hundred regions of volcanic activity known as hot spots. Unlike most volcanoes, hot spots are rarely found along the boundaries of the continental and oceanic plates that comprise the Earth's crust; most hot spots lie deep in the interior of plates and are anchored deep in the layers of the earth's surface. Hot spots are also distinguished from other volcanoes by their lavas, which contain greater amounts of alkali metals than do those from volcanoes at plate margins.
In some cases, plates moving past hot spots have left trails of extinct volcanoes in much the same way that wind passing over a chimney carries off puffs of smoke. It appears that the Hawaiian Islands were created in such a manner by a single source of lava, welling up from a hot spot, over which the Pacific Ocean plate passed on a course roughly from the east toward the northwest, carrying off a line of volcanoes of increasing age. Two other pacific island chains- the Austral Ridge and the Tuamotu Ridge-parallel the configuration of the Hawaiian chain; they are also aligned from the east toward the northwest, with the most recent volcanic activity near their eastern terminuses.
That the Pacific plate and the other plates are moving is now beyond dispute; the relative motion of the plates has been reconstructed in detail. However, the relative motion of the plates with respect to the Earth's interior cannot be determined easily. Hot spots provide the measuring instruments for resolving the question of whether two continental plates are moving in opposite directions or whether one is stationary and the other is drifting away from it. The most compelling evidence that a continental plat is stationary is that, at some hot spots, lavas of several ages are superposed instead of being spread out in chronological sequence. Of course, reconstruction of plate motion from the tracks of hot-spot volcanoes assumes that hot spots are immobile, or nearly so. Several studies support such an assumption, including one that has shown that prominent hot spots through- out the world seem not to have moved during the past ten million years.
Beyond acting as frames of reference, hot spots apparently influence the geophysical processes that propel the plates across the globe. When a continental plate comes to rest over a hot spot, material welling up from deeper layers forms a broad dome that, as it grows, develops deep fissures. In some instances, the continental plate may rupture entirely along some of the fissures so that hot spot initiates the formation of a new ocean. Thus, just as earlier theories have explained the mobility of the continental plates, so hot-spot activity may suggest a theory to explain their mutability
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