|
Magoosh
|
How many three-digit numbers are there such that all three digits are different and the first digit is not zero?
|
|
Magoosh
|
David drove to work at an average (arithmetic mean) speed of 45 miles per hour. After work, David drove home at an average speed of 60 miles per hour. If David spent a total of 2 hours commuting to and from work, how many miles does David drive to work?
|
|
|
The historical basis for the King Arthur legend has long been debated by scholars. One school of thought, citing entries in the History of the Britons and Welsh Annals, sees Arthur as a genuine historical figure, a Romano-British leader who fought against the invading Anglo-Saxons sometime in the late 5th to early 6th century. The other text that seems to support the case for Arthur's historical existence is the 10th-century Annales Cambriae. The latest research shows that the Annales Cambriae was based on a chronicle begun in the late 8th century in Wales. Additionally, the complex textual history of the Annales Cambriae precludes any certainty that the Arthurian annals were added to it even that early. They were more likely added at some point in the 10th century and may never have existed in any earlier set of annals. This lack of convincing early evidence is the reason many recent historians exclude Arthur from their accounts of post-Roman Britain. In the view of historian Thomas Charles-Edwards there may well have been an historical Arthur, but that a historian can as yet say nothing of value about him. These modern admissions of ignorance are a relatively recent trend; earlier generations of historians were less skeptical. Historian John Morris made the putative reign of Arthur the organizing principle of his history of post-Roman Britain and Ireland. Even so, he found little to say about a historical Arthur. Partly in reaction to such theories, another school of thought emerged which argued that Arthur had no historical existence at all. Morris's Age of Arthur prompted archaeologist Nowell Myres to observe that no figure on the borderline of history and mythology has wasted more of the historian's time. Arthur is not mentioned in the Anglo-Saxon Chronicle or named in any surviving manuscript written between 400 and 820. He is absent from Bede's early-8th-century Ecclesiastical History of the English People, another major early source for post-Roman history. Some scholars argue that Arthur was originally a fictional hero of folklore—or even a half-forgotten Celtic deity—who became credited with real deeds in the distant past. They cite parallels with figures such as the Kentish totemic horse-gods Hengest and Horsa, who later became historicized. Bede ascribed to these legendary figures a historical role in the 5th-century Anglo-Saxon conquest of eastern Britain. Historical documents for the post-Roman period are scarce. Of the many post-Roman archeological sites and places, only a handful have been identified as "Arthurian," and these date from the 12th century or later. Archaeology can confidently reveal names only through inscriptions found in reliably dated sites. In the absence of new compelling information about post-Roman England, a definitive answer to the question of Arthur's historical existence is unlikely.
|
|
Magoosh
|
Given$$f(x)= {{x}\over{x+1}}$$, for what value k does $$f(f(k))=\frac{2}{3}?$$
|
|
Magoosh
|
If ABCD is a rectangle, BC = x and AB = 2x, then the circumference of the circle, in terms of x, is
|
|
Magoosh
|
Nowell Myres would most likely view the idea of an Arthurian reign as key to the understanding of the history of sub-Roman Briton as
|
|
Magoosh
|
The author most likely mentions Bede's Ecclesiastical History of the English People in order to
|
|
Magoosh
|
According to the passage, Bede's Ecclesiastical History of the English People contains information that
|
|
Magoosh
|
Ⅰ.$${49！}\over{({7^{49})}^{2}}$$Ⅱ.$${49！}\over（{7！）^{2}}$$Ⅲ.$${49！}\over（{42！）（7！）}$$Rank these three quantities from least to greatest.
|
|
|
People associate global warming with temperature, but the phrase is misleading—it fails to mention the relevance of water. Nearly every significant indicator of hydrological activity—rainfall, snowmelt, glacial melt—is changing at an accelerating pace (one can arbitrarily pick any point of the hydrological cycle and notice a disruption). One analysis pegged the increase in precipitation at 2 percent over the century. In water terms this sounds auspicious, promising increased supply, but the changing timing and composition of the precipitation more than neutralizes the advantage. For one thing, it is likely that more of the precipitation will fall in intense episodes, with flooding a reasonable prospect. In addition, while rainfall will increase, snowfall will decrease. Such an outcome means that in watersheds that depend on snowmelt, like the Indus, Ganges, Colorado river basins, less water will be stored as snow, and more of it will flow in the winter, when it plays no agricultural role; conversely, less of it will flow in the summer, when it is most needed. One computer model showed that on the Animas River an increase in temperature of 3.6 degrees Fahrenheit would cause runoff to rise by 85 percent from January to March, but drop by 40 percent from July to September. The rise in temperature increases the probability and intensity of spring floods and threatens dam safety, which is predicated on lower runoff projections. Dams in arid areas also may face increased sedimentation, since a 10 percent annual increase in precipitation can double the volume of sediment washed into rivers. The consequences multiply. Soil moisture will intensify at the highest northern latitudes, where precipitation will grow far more than evaporation and plant transpiration but where agriculture is nonexistent. At the same time, precipitation will drop over northern mid-latitude continents in summer months, when ample soil moisture is an agricultural necessity. Meanwhile the sea level will continue to rise as temperatures warm, accelerating saline contamination of freshwater aquifers and river deltas. The temperature will cause increased evaporation, which in turn will lead to a greater incidence of drought. Perhaps most disturbing of all, the hydrologic cycle is becoming increasingly unpredictable. This means that the last century's hydrological cycle—the set of assumptions about water on which modern irrigation is based—has become unreliable. Build a dam too large, and it may not generate its designed power; build it too small, and it may collapse or flood. Release too little dam runoff in the spring and risk flood, as the snowmelt cascades downstream with unexpected volume; release too much and the water will not be available for farmers when they need it. At a time when water scarcity calls out for intensified planning, planning itself may be stymied.
|
|
Magoosh
|
Based on information in the second paragraph, which of the following can best be supported?
|
|
Magoosh
|
The passage is primarily concerned with
|
|
Magoosh
|
If k is an integer, what is the smallest possible value of k such that 1040k is the square of an integer?
|
|
Magoosh
|
The passage implies which of the following about volcanoes on Mars?
|
|
Magoosh
|
The author of the passage considers Morgan's plan to educate corporations “shortsighted” since it
|
|
Magoosh
|
According to the passage, which of the following is common to both Peavy's and Morgan's studies?
|
|
|
Researchers, investigating the link between daily coffee consumption and learning, claim that subjects who consumed one cup of coffee a day for one week (the equivalent of 50 mg per day) exhibited improvements in declarative memory. Furthermore, the study revealed that such improvements were longer-lasting than those witnessed in a control group served decaffeinated coffee (decaffeinated contains negligible amounts of caffeine). After a week of learning a list of facts, the subjects who consumed one cup of coffee were able to recall these facts with significantly more accuracy. While daily coffee consumption may aid in the process of forming a greater number of short-term memories, and increase the likelihood that these memories will be stored in long-term memory, the study glosses over an important fact. Many exhibit sensitivities to caffeine, including headaches (both migraine and non-migraine), sleeplessness, heightened anxiety and any number of factors that, when working either alone or in tandem, may actually lead to a decrease in the observed link between caffeine and learning. Nonetheless, despite the fact that the study represents a random sampling—and thus any number of subjects can exhibit any number of reactions to caffeine—if enough subjects continue to display signs of improvements in learning, then this result would not be inconsistent with the study's findings. Still, until the researchers either release more details of this study, or subsequent studies are conducted, the extent to which those with caffeine sensitivity influenced the observed link between coffee consumption and memory will not be fully known.
|
|
Magoosh
|
In describing the range of negative reactions of subjects with caffeine sensitivities, the author implies that
|
|
Magoosh
|
According to the passage, the observed results of the study are not inconsistent with the fact that any number of subjects could exhibit caffeine sensitivities because
|
|
Magoosh
|
The most immediate effect on birds that have accumulated toxins in their fat deposits is
|