Adapted from "The Greatest Sea-Wave Ever Known" by R. A. Proctor in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

The inhabitants of the Sandwich Islands, which lie about six thousand three hundred miles from Arica—a city in Chile, might have imagined themselves safe from any effects that could be produced by an earthquake taking place so far away from them. But on the night between August 13th and 14th, the sea around this island group rose in a surprising manner, and many thought the islands were sinking, and would shortly subside altogether beneath the waves. Some of the smaller islands, indeed, were for a time completely submerged. Before long, however, the sea fell again, and as it did so the observers "found it impossible to resist the impression that the islands were rising bodily out of the water." For no less than three days this strange oscillation of the sea continued to be experienced, the most remarkable ebbs and floods being noticed at Honolulu, on the island of Woahoo.

But the sea-wave swept onward far beyond these islands. At Yokohama, in Japan, more than ten thousand five hundred miles from Arica, an enormous wave poured in on August 14th, but at what hour we have no satisfactory record. So far as distance is concerned, this wave affords most surprising evidence of the stupendous nature of the disturbance to which the waters of the Pacific Ocean had been subjected. The whole circumference of the earth is but twenty-five thousand miles, so that this wave had traveled over a distance considerably greater than two-fifths of the earth's circumference. A distance which the swiftest of our ships could not traverse in less than six or seven weeks had been swept over by this enormous undulation in the course of a few hours.

The primary point of this essay is that __________.

"Cacti" by Ami Dave (2013)

Cacti are plants suited to the desert, and we must always keep this factor in mind when growing ornamental cacti in our gardens, for it helps us provide cacti with conditions that allow them to survive and thrive. For example, a cactus should never be watered over its body, as it will start to rot. This is because it is covered with a waxy coating which prevents water loss through evaporation. When one waters the cactus over its body, the waxy coating is washed away and the plant begins to rot. The amount of water that one must supply to the cactus is very much dependent upon the season and upon the climate of the place. During the summer season one should water cacti every four days, whereas in the rainy season, once every fifteen days is quite enough.

Cacti need a minimum of two and a half hours of sunlight per day; however, they should not be kept in the sun all day because they may wrinkle when exposed to too much bright sunlight. Unlike other plants, cacti produce carbon dioxide during the day and oxygen during the night, so they are ideal plants to be kept in bedrooms to freshen up the air at night.

If a cactus is to thrive and prosper, the size of the pot in which it is grown needs to be monitored carefully. The pot should always be a little smaller than the plant itself because it is only when the plant has to struggle to survive that it will thrive. If the pot is too spacious and the plant does not need to struggle, chances are that the cactus will die. Similarly, if a cactus shows no signs of growth, stop watering it. Watering should be resumed only when the plant begins to grow again.

The substrata of a cactus pot is ideally composed of pieces of broken bricks at the bottom, followed by a layer of charcoal above the bricks, and then coarse sand and pebbles above the charcoal. Leaf mould is the best manure.

Grafting cacti is very simple. A very small piece of the cactus plant should be stuck with tape to the plant that needs grafting. The smaller the piece, the easier it is to graft. To reproduce cacti, one has to simply cut off a piece of the cactus, allow it to dry for a few days, and then place it over the cacti substrate. It will automatically develop roots.

It is very easy to differentiate between cacti and other plants that look like cacti. All cacti have fine hair at the base of each thorn. The so-called “thorns” are in fact highly modified leaves which prevent loss of water through transpiration. If one ever gets pricked by cacti thorns, one should take tape, place it over the area where the thorns have penetrated the skin, and then peel it off. All of the thorns will get stuck to the tape and will be removed.

The purpose of this passage is to __________.

Adapted from "How Animals Spend the Winter" by W. S. Blatchley in A Book of Natural History (1902, ed. David Starr Jordan)

One of the greatest problems that each of the living forms about us has had to solve, during the years of its existence on earth, is how best to perpetuate its kind during that cold season that once each year, in our temperate zone, is bound to come. Many are the solutions to this problem. Each form of life has, as it were, solved it best to suit its own peculiar case, and to the earnest student of Nature there is nothing more interesting than to pry into these solutions and note how varied, strange, and wonderful they are.

To fully appreciate some of the facts mentioned below it must be borne in mind that there is no such thing as “spontaneous generation” of life. Every cell is the offspring of a pre-existing cell. Hence every weed that next season will spring up and provoke the farmer’s ire, and every insect that will then make life almost intolerable for man or beast, exists throughout the winter in some form.

Beginning with the earthworms and their kindred, we find that at the approach of winter they burrow deep down where the icy breath of the frost never reaches, and there they live, during the cold season, a life of comparative quiet. That they are exceedingly sensitive to warmth, however, may be proven by the fact that when a warm rain comes some night in February or March, thawing out the crust of the earth, the next morning reveals in our dooryards the mouths of hundreds of the pits or burrows of these primitive tillers of the soil, each surrounded by a little pile of pellets, the castings of the active artisans of the pits during the night before.

If we will get up before dawn on such a morning we can find the worms crawling actively about over the surface of the ground, but when the first signs of day appear they seek once more their protective burrows, and only an occasional belated individual serves as a breakfast for the early birds.

The third paragraph is concerned with __________.

Adapted from "Rain and Snow" by John Tyndall in Wonders of Earth, Sea, and Sky (1902, ed. by Edward Singleton Holden)

At the equator, and within certain limits north and south of it, the sun at certain periods of the year is directly overhead at noon. These limits are called the Tropics of Cancer and of Capricorn. Upon the belt comprised between these two circles, the sun's rays fall with their mightiest power, for here they shoot directly downwards and heat both earth and sea more than when they strike slantingly. When the vertical sunbeams strike the land, they heat it, and the air in contact with the hot soil becomes heated in turn. But when heated, the air expands, and when it expands, it becomes lighter. This lighter air rises through the heavier air overhead.

When the sunbeams fall upon the sea, the water is warmed, though not so much as the land. The warmed water expands, becomes thereby lighter, and therefore continues to float upon the top. This upper layer of water warms to some extent the air in contact with it, but it also sends up a quantity of aqueous vapor, which being far lighter than air helps the latter to rise. Thus both from the land and from the sea we have ascending currents established by the action of the sun.

The primary function of this passage is __________.

Adapted from A Catechism of Familiar Things: Their History and the Events Which Led to Their Discovery by the Benziger Brothers (1881)

Twilight is the light from the first dawning of day to the rising of the sun; and again between its setting and the last remains of day. Without twilight, the sun's light would appear at its rising, and disappear at its setting, instantly; and we should experience a sudden transition from the brightest sunshine to the most complete obscurity. The duration of twilight is different in different climates; and in the same places it varies at different periods of the year.

This passage is primarily concerned with __________.

Adapted from "The Greatest Sea-Wave Ever Known" by R. A. Proctor in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

It was at Arequipa, at the foot of the lofty volcanic mountain Misti, that the most terrible effects of the great earthquake were experienced. Within historic times, Misti has poured forth no lava streams, but that the volcano is not extinct is clearly evidenced by the fact that in 1542 an enormous mass of dust and ashes was vomited forth from its crater. On August 13th, 1868, Misti showed no signs of being disturbed. So far as the volcanic neighbor was concerned, the forty-four thousand inhabitants of Arequipa had no reason to anticipate the catastrophe which presently befell them.

At five minutes past five, an earthquake shock was experienced, which, though severe, seems to have worked little mischief. Half a minute later, however, a terrible noise was heard beneath the earth; a second shock more violent than the first was felt, and then began a swaying motion, gradually increasing in intensity. In the course of the first minute, this motion had become so violent that the inhabitants ran in terror out of their houses into the streets and squares. In the next two minutes, the swaying movement had so increased that the more lightly built houses were cast to the ground, and the flying people could scarcely keep their feet. "And now," says Von Tschudi, "there followed during two or three minutes a terrible scene. The swaying motion changed into fierce vertical upheaval. The subterranean roaring increased in the most terrifying manner; then were heard the heart-piercing shrieks of the wretched people, the bursting of walls, the crashing fall of houses and churches, while over all rolled thick clouds of a yellowish-black dust, which, had they been poured forth many minutes longer, would have suffocated thousands." Although the shocks had lasted but a few minutes, the whole town was destroyed. Not one building remained uninjured, and there were few that did not lie in shapeless heaps of ruins.

The focus of the essay at the beginning of this passage is primarily on __________.

Adapted from "The Greatest Sea-Wave Ever Known" by R. A. Proctor in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

It was at Arequipa, at the foot of the lofty volcanic mountain Misti, that the most terrible effects of the great earthquake were experienced. Within historic times, Misti has poured forth no lava streams, but that the volcano is not extinct is clearly evidenced by the fact that in 1542 an enormous mass of dust and ashes was vomited forth from its crater. On August 13th, 1868, Misti showed no signs of being disturbed. So far as the volcanic neighbor was concerned, the forty-four thousand inhabitants of Arequipa had no reason to anticipate the catastrophe which presently befell them.

At five minutes past five, an earthquake shock was experienced, which, though severe, seems to have worked little mischief. Half a minute later, however, a terrible noise was heard beneath the earth; a second shock more violent than the first was felt, and then began a swaying motion, gradually increasing in intensity. In the course of the first minute, this motion had become so violent that the inhabitants ran in terror out of their houses into the streets and squares. In the next two minutes, the swaying movement had so increased that the more lightly built houses were cast to the ground, and the flying people could scarcely keep their feet. "And now," says Von Tschudi, "there followed during two or three minutes a terrible scene. The swaying motion changed into fierce vertical upheaval. The subterranean roaring increased in the most terrifying manner; then were heard the heart-piercing shrieks of the wretched people, the bursting of walls, the crashing fall of houses and churches, while over all rolled thick clouds of a yellowish-black dust, which, had they been poured forth many minutes longer, would have suffocated thousands." Although the shocks had lasted but a few minutes, the whole town was destroyed. Not one building remained uninjured, and there were few that did not lie in shapeless heaps of ruins.

The focus of the essay towards the end of this passage is primarily on __________.

Adapted from "Some Strange Nurseries" by Grant Allen in A Book of Natural History (1902, ed. David Starr Jordan)

Many different types of animals employ one of two strategies in raising their young. Certain animals, called “r-strategists,” turn out thousands of eggs with reckless profusion, but they let them look after themselves, or be devoured by enemies, as chance will have it. Other animals, called “K-strategists,” take greater pain in the rearing and upbringing of the young. Large broods indicate an “r” life strategy; small broods imply a “K” life strategy and more care in the nurture and education of the offspring. R-strategists produce eggs wholesale, on the off chance that some two or three among them may perhaps survive an infant mortality of ninety-nine per cent, so as to replace their parents. K-strategists produce half a dozen young, or less, but bring a large proportion of these on an average up to years of discretion.

Which of these extracts best captures the main idea of this passage?

"Abstraction in the Sciences" by Matthew Minerd (2014)

Thinking “abstractly” is not a term that means quite the same thing in all of the sciences. Although we rarely think about this, it plays a key role in almost all of our day-to-day thought. Consider a zoologist working in a lab with many animals. When she is studying any individual tiger, she is not completely worried about the particular tiger—at least not primarily. Instead, she is trying to figure out certain characteristics of tigers in general. By meticulous testing, the zoologist carefully works out the physiology of tigers and considers what are absolutely necessary elements of their physical makeup. Even when she places a tiger in different habitats, her sight is aimed at the general condition of tigers and their needs in general.

However, things become even stranger when you start to consider how we think about mathematical objects. Consider the case of geometric figures. A triangle appears to be rather simple for most of us to think about. You can draw a triangle on a piece of paper, each side having a certain thickness and length. However when you think about this in geometry class, the triangle’s edges have no real thickness. Neither a point nor a line has a thickness for the mathematician. Such a thickness only exists on our paper, which represents the point or line. Consider also a line drawn on a piece of graph paper. Technically, there are an infinite number of points in the line. Indeed, even between 4.5 and 4.6, there are an infinite number of numbers—for example 4.55 is between them, then 4.555 between 4.55 and 4.6, and 4.5555 between 4.555 and 4.6, et cetera. In all of these cases, the mathematical reality takes on a very peculiar character when you consider it in the abstract. However, the concrete triangle remains very tangible and ordinary. Likewise, 4.6 and 4.5 inches still have 0.1 inches between them. Nevertheless, in the abstract, mathematical realities are quite strange, even stranger then the idea of “a tiger in general.”

Which of the following would strengthen the ending of the first paragraph?

Adapted from “Comets” by Camille Flammarion in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

The history of a comet would be an instructive episode of the great history of the heavens. In it could be brought together the description of the progressive movement of human thought, as well as the astronomical theory of these extraordinary bodies. Let us take, for example, one of the most memorable and best-known comets, and give an outline of its successive passages near the Earth. Like the planetary worlds, comets belong to the solar system, and are subject to the rule of the Star King. It is the universal law of gravitation which guides their path; solar attraction governs them, as it governs the movement of the planets and the small satellites. The chief point of difference between them and the planets is that their orbits are very elongated, and instead of being nearly circular, they take the elliptical form. In consequence of the nature of these orbits, the same comet may approach very near the sun, and afterwards travel from it to immense distances.

Thus, the period of the Comet of 1680 has been estimated at three thousand years. It approaches the sun, so as to be nearer to it than our moon is to us, whilst it recedes to a distance 853 times greater than the distance of the Earth from the sun. On the 17th of December, 1680, it was at its perihelion—that is, at its greatest proximity to the sun; it is now continuing its path beyond the Neptunian orbit. Its velocity varies according to its distance from the solar body. At its perihelion it travels thousands of leagues per minute; at its aphelion it does not pass over more than a few yards.

Its proximity to the Sun in its passage near that body caused Newton to think that it received a heat twenty-eight thousand times greater than that we experience at the summer solstice, and that this heat being two thousand times greater than that of red-hot iron, an iron globe of the same dimensions would be fifty thousand years entirely losing its heat. Newton added that in the end, comets will approach so near the sun that they will not be able to escape the preponderance of its attraction, and that they will fall one after the other into this brilliant body, thus keeping up the heat which it perpetually pours out into space. Such is the deplorable end assigned to comets by the author of the Principia, an end which makes De la Brétonne say to Rétif: "An immense comet, already larger than Jupiter, was again increased in its path by being blended with six other dying comets. Thus displaced from its ordinary route by these slight shocks, it did not pursue its true elliptical orbit; so that the unfortunate thing was precipitated into the devouring centre of the Sun." "It is said," added he, "that the poor comet, thus burned alive, sent forth dreadful cries!"

The primary purpose of the second paragraph is to __________.