Environment and societal development

Port Sela is the only city shown with the "over 1,000,000 people" symbol. The map shows that it sits on the coast of the Western Ocean, right where the Amon River flows into it, in the grassland plains.

Reasoning:

1. A river mouth on the coast lets goods travel inland by river and overseas by ship, so the city becomes a trading hub.
2. The surrounding grassland plains are flat land with 20–40 inches of rain, which is good for farming to feed a large population.
3. Big cities around the world (New Orleans, Shanghai, Rotterdam) grew at river mouths for the same reasons.

The correct answer is C.

Why not the others? A is wrong because the mountains are in columns E–F, far from Port Sela. B describes Halven, not Port Sela. D is wrong because the forest covers the north (row 1), not the coast at row 3.

Tip: to explain where a city is, check the map for water (coast, river), land type (flat or steep), and resources. Access to water transportation is the most common reason for large cities.

Use the legend to identify what surrounds Halven.

Step by step:

1. Halven is in square E4, among the mountain symbols.
2. Right next to Halven is an ✕ symbol. The legend says ✕ means copper mine.
3. Halven is a small town (under 250,000) far from the coast and the river, so fishing and river trade are unlikely. It is also not in the forest (row 1) or on flat farmland.

A mountain town next to a mine most likely depends on mining copper.

The correct answer is A.

Tip: on thematic maps, every symbol is in the legend for a reason. When a question asks about a place, look at the symbols touching that place and translate each one with the legend before choosing an answer.

Read the map: Dunmore is in square E4, in the desert (the dotted area across row 4). Black squares surround it. The legend shows that a black square means oil wells.

Reasoning: Few people would choose to live in a desert, which has little water for farming. A resource such as oil gives people a reason to settle there and provides jobs. So oil drilling is most likely an important activity in Dunmore.

The correct answer is C.

Why not the others? A: the fishing symbols are in the ocean along the west coast, far from Dunmore. B: the forest is in row 1, near Pinecrest. D: farmland lies along the Tamar River in row 3, not in the desert.

Tip: always match each symbol on the map to the legend before answering, and look only at the symbols next to the place named in the question.

Read the key: darker shading means more rain; the lightest shade means less than 10 inches a year.

Read the map: the lightest counties are Ash and Elm (the western column) and Fenn (in the south, second from the west). All three are on the western side of the state. The darkest counties, Dover and Harbor, are on the eastern coast.

The correct answer is B, the western counties.

Why not the others? A: the eastern coast (Dover and Harbor) gets the most rain, more than 30 inches. C: the north row runs from the driest (Ash) to the wettest (Dover), so it is not the driest part as a whole. D: Gale is in the 20–30-inch range, much wetter than the west.

Tip: on a shaded (choropleth) map, check the key first to learn whether dark means more or less. Then look for where the extreme shades cluster.

Evidence: Paragraph 4: "In 1953, a powerful storm pushed the North Sea over the dikes. More than 1,800 people died. In response, the government built the Delta Works."

Reasoning: The words "In response" signal cause and effect. The cause was the deadly 1953 flood; the effect was the Delta Works, a system of dams, barriers, and storm gates.

The correct answer is A.

Why not the others? B describes the Room for the River program in paragraph 5, a later and different response. C is a side effect of draining the land (paragraph 3), but the passage does not name it as the reason for the Delta Works. D reverses the passage: windmills were replaced by electric pumps, not by the Delta Works.

Tip: signal words such as in response, as a result, because, and led to mark cause and effect. Find them first on cause-and-effect questions.

Read the chart: the Amon River Valley gets 28 inches of rain a year, less than the Central Plains (30) and the Eastern Mountains (35). Yet its density is 240 people per square mile, far above the plains (60) and the mountains (8).

Read the map: the Amon River flows through the valley from the mountains to the ocean, and two of the biggest cities, Port Sela and Darro, sit on it.

Reasoning: the river supplies water for drinking and irrigation no matter how much rain falls. It also provides a route for transportation and trade. Flat land beside a river is ideal for farming and building. These advantages attract people.

The correct answer is B.

Why not the others? A contradicts the chart (the valley has less rain). C describes Halven, a small mountain town, not the valley. D contradicts the chart: the Eastern Mountains have only 8 people per square mile.

Tip: when data show an exception to a pattern, look at the map for a physical feature (river, coast, mountain, oasis) that explains it. GED questions often pair a chart with a map for exactly this reason.

Check each region's rainfall against its population density:

Reasoning:

• The Northern Forest gets the most rain (48 in.) but has only 15 people per square mile.
• The Eastern Mountains get 35 in. but have only 8 people per square mile.
• The Amon River Valley gets less rain (28 in.) yet has the most people (240).

So more rain does not always mean more people. Other factors, such as rivers, flat land, and steep terrain, also shape where people live.

The correct answer is D.

Why not the others? A is contradicted by the forest and the mountains. B misreads the chart: the desert has the least rain (7 in.), not the mountains. C uses an absolute word ("no one"), but the desert has 4 people per square mile, not zero.

Tip: a single counterexample disproves an "always" pattern. Before accepting a trend, check every bar, and be suspicious of answers with no one, all, always, or never.

The dust storms had both human and natural causes.

Evidence:

• Paragraph 1 (human cause): farmers plowed "millions of acres of grassland," removing the "deep-rooted prairie grasses" that "had held the soil in place."
• Paragraph 2 (natural causes): "a severe drought struck," and "With the grass gone, nothing held down the dry, loose topsoil. Strong winds lifted it into enormous dust storms."

Reasoning: grassland had survived dry spells for thousands of years. The storms came when plowing removed the grass and then drought and wind hit the bare soil. Neither cause alone fully explains the disaster.

The correct answer is A.

Why not the others? B leaves out the human cause; the passage stresses that the grass had protected the soil during earlier dry spells. C confuses cause and response: the Soil Conservation Service came after the storms, to fix the problem. D is not in the passage; people leaving was an effect of the storms, not a cause.

Tip: in cause-and-effect questions, keep causes, effects, and responses in order. A common trap swaps an effect or a later response into the cause position.

Roosevelt's excerpt has two parts.

1. First, he grants a point: "We have become great in a material sense because of the lavish use of our resources, and we have just reason to be proud of our growth."
2. Then he turns with "But": "the time has come to inquire seriously what will happen when our forests are gone, when the coal, the iron, the oil, and the gas are exhausted, when the soils shall have been still further impoverished…"

Reasoning: the main concern comes after the turn. He worries that wasteful use will use up or ruin the nation's natural resources — forests, minerals, fuels, and soil — and he wants the country to plan for the future. This is the central idea of the conservation movement.

The correct answer is C.

Why not the others? A repeats the part he grants before "But." It is true, but it is not his concern. B overstates; he asks people to "inquire seriously," not to stop all use. D is one detail (blocked navigation) that is just one example of damaged soil, not the main idea.

Tip: in speeches and arguments, words like but, however, and yet often signal the author's real point. The main idea covers the whole excerpt, not one example.

Evidence: Source 1, paragraph 3: "The land here is plentiful; the water is not. The amount of land that can be farmed is limited by the water in the streams." Paragraph 1 adds that the rain is "too little for the kind of farming practiced in the East."

Reasoning: Every paragraph supports one central point: on the dry plains, water, not land, limits how much farming and settlement are possible. Paragraph 2 rejects the hope that plowing will bring rain, and paragraph 3 recommends matching settlement to the water supply.

The correct answer is D.

Why not the others? A is the land agents' claim, which the surveyor rejects. B is the opposite of the surveyor's recommendation to limit settlers to the water available. C is a detail: farms reaching a stream is one recommendation, not the main idea, and nothing says farms should be larger.

Tip: the main idea is the point that all paragraphs support. A choice that matches only one sentence is usually a detail, and a choice that matches someone the author argues against is a trap.

Evidence:

• Paragraph 1: the floods "spread fertile silt over farm fields."
• Table: silt reaching the delta fell from 85 to 9 million tons a year, while chemical fertilizer used by downstream farms rose from 5,000 to 42,000 tons a year.

Reasoning: Before the dam, the river delivered natural fertilizer (silt) every year. After the dam trapped the silt, farmers bought far more chemical fertilizer. The data and the text together support the conclusion that farmers replaced the lost silt with chemical fertilizer.

The correct answer is B.

Why not the others? A reverses cause and effect: the fertilizer did not reduce the silt; the dam did (paragraph 3). C is not supported; irrigated farmland more than doubled, so farming did not stop. D contradicts the data: less silt reached the delta.

Tip: when two rows of a table change at the same time, use the text to decide which is the cause. Here the text says the dam trapped the silt.

Test each statement against the map.

• A. Farmland (yellow shading) covers row 3 from the coast through column D, right along the Tamar River. Supported. Rivers provide water and fertile soil, so farmland often lines them.
• B. The oil well symbols (black squares) are in the desert of row 4, not in the mountains. Not supported.
• C. The forest (dark green) covers row 1 in the north, not the south. Not supported.
• D. Iron ore (gray diamonds) is in the mountains of columns E and F, far from the coast. Not supported.

The correct answer is A.

Tip: on "which statement is supported" map questions, check every choice; each wrong one usually puts a real feature in the wrong place. Also notice the pattern behind the right answer: farmland follows water.

Read the map row by row, west to east:

• North row: Ash (less than 10 in.) → Birch (10–20) → Cedar (20–30) → Dover (more than 30).
• South row: Elm (less than 10) → Fenn (less than 10) → Gale (20–30) → Harbor (more than 30).

In both rows, the shading gets darker toward the east, where the ocean is. So rainfall generally increases from west to east. (In the south row, Elm and Fenn are both in the driest category, but the overall direction still runs from dry west to wet east.)

The correct answer is C.

Why not the others? A: the north and south rows have nearly the same categories, so there is no north–south pattern. B reverses the direction. D is wrong because the counties fall into four different categories.

Tip: a "pattern" question asks about the whole map, not one county. Trace the colors along one direction at a time (west to east, then north to south) and see which direction shows a steady change.

Combine the two sources for the six inland counties:

Reasoning: The driest counties raise cattle, which can graze on dry grassland. The wettest inland counties grow corn and soybeans, which need more water. Fenn grows crops despite being dry, but the table says its crops are irrigated, and the map shows the Silver River flowing through it. So the pattern holds: where rain is scarce, crops need another water source.

The correct answer is A.

Why not the others? B reverses the pattern. C overlooks the table: ranching and crops are both present. D ignores the map: Dover and Harbor depend on the ocean, but they are not inland, and inland activities clearly vary with rainfall.

Tip: when a question names two sources, build a small table that lines up the facts from each source for the same places.

Evidence: Paragraph 3: "Without new silt, waves wear away the delta's shoreline faster than the river can rebuild it." The table shows shoreline loss jumped from 2 to 30 feet a year after silt reaching the delta fell from 85 to 9 million tons.

Reasoning: If more silt passes the dam, the river can again rebuild the delta. So the delta should lose land more slowly. Paragraph 3 also says the fish fed on nutrients carried by the silt, so fish catches might improve too.

The correct answer is C.

Why not the others? A: silt does not control flooding; the dam's ability to hold back water would not change. B: electricity comes from water turning the dam's turbines, and the passage does not connect it to silt. D reverses the logic: more silt brings natural fertilizer, so farmers would likely need less chemical fertilizer, not more.

Tip: to predict the effect of a change, find the cause-and-effect chain in the text (less silt → shoreline loss) and run it in reverse (more silt → less loss).

Definitions:

• Modify = people physically change the land or water (build, drain, dam).
• Adapt = people change their own homes or habits to fit the conditions.

Evidence: Paragraph 5: "In some cities, families live in floating houses that rise and fall with the water." The water level is not changed at all. Instead, the houses are designed to fit the rising and falling water. That is adapting.

The correct answer is B.

Why not the others? A (building dikes and draining lakes), C (dams, barriers, and storm gates), and D (raising and strengthening dikes) all physically change the coast or the water, so they are examples of modifying the environment. Large engineering projects are almost always modification.

Tip: ask what is being changed: the environment, or the people? If the environment is reshaped, it is modification.

Source 1: Roosevelt warned of a time "when the soils shall have been still further impoverished and washed into the streams" — in other words, soil erosion and wasted farmland.

Source 2: the Dust Bowl was exactly that kind of soil loss. In paragraph 4, "Congress created the Soil Conservation Service to teach farmers methods such as contour plowing, crop rotation, and planting rows of trees as windbreaks," and "these practices helped hold the soil in place."

Reasoning: the Soil Conservation Service is a government effort to protect soil for the future — the conservation idea Roosevelt promoted in 1908.

The correct answer is D.

Why not the others?

• A describes plowing grassland, which caused the erosion Roosevelt feared.
• B (rising wheat prices) is an economic cause of the plowing, not a response.
• C (families moving to California) is a consequence of the disaster, not an effort to protect soil.

Tip: on paired-source questions, restate the first source's idea in plain words (here: don't let soil wash away), then look for the part of the second source that matches that idea, not just shares a topic.

Source 1's warning: "The land here is plentiful; the water is not. The amount of land that can be farmed is limited by the water in the streams."

Source 2's evidence: paragraph 3: "In many areas, farmers pump water out much faster than nature replaces it. In parts of Kansas and Texas, the water level has dropped by more than 100 feet, and some wells have gone dry."

Reasoning: The new source of water (the aquifer) let farming expand, but it is being used up. Falling water levels and dry wells show that water still limits farming, exactly as the surveyor warned.

The correct answer is D.

Why not the others? A and C describe successes of irrigation; on their own, they seem to show the opposite of the warning. B is a geographic fact about the aquifer, but it says nothing about water running short.

Tip: to connect two sources, first state the first source's key idea in your own words. Then look for the detail in the second source that matches or tests that idea directly.

Evidence: Source 1, paragraph 2: "Some land agents tell settlers that rain will follow the plow ... I have found no evidence to support this belief."

Reasoning: The idea belongs to the land agents, not to the surveyor. The surveyor reports that he found no evidence for it, and in paragraph 3 he recommends limiting settlement to the water available. His attitude is skeptical: he does not accept the claim without evidence.

The correct answer is B.

Why not the others? A confuses the surveyor's view with the land agents' view. C: the surveyor never asks for more study; he says he found no evidence and moves on to recommendations based on water supply. D: he does not say the belief is true in wet years; he says the plains get too little rain in most years.

Tip: on point-of-view questions, separate the author's own opinion from the views the author reports about other people. Phrases like "some people say" signal a view the author may reject.

Check each statement against the table.

• A. "The dam ended all major flooding downstream." The table shows major floods fell from 6 to 1 per ten years. Floods became much rarer, but they did not end. Not supported.
• B. "Irrigated farmland more than tripled." 120{,}000 \times 3 = 360{,}000, and the new value is 310,000. That is more than double but less than triple. Not supported.
• C. "The fish catch fell to about one-quarter of its earlier level." 18{,}000 \div 4 = 4{,}500, exactly the new value. Supported.
• D. "Chemical fertilizer caused the shoreline to wear away." The table shows both rose, but the text explains the shoreline loss by missing silt, not by fertilizer. The table alone cannot show that fertilizer is the cause. Not supported.

The correct answer is C.

Tip: on data questions, test every number in a choice with quick math, and be suspicious of absolute words (all, never, ended) and of cause-and-effect claims drawn only from two numbers rising together.

Work backwards from the distance: each grid square is 50 miles, so 150 miles = 150 \div 50 = 3 squares.

Check each pair:

• A. Pinecrest to Granite Falls: both in row 1; Pinecrest is in the middle of column B and Granite Falls in the middle of column E. That is 3 squares east–west = about 150 miles. ✔
• B. Bayport to Millford: 2 squares along row 3 = about 100 miles.
• C. Bayport to Dunmore: 4 squares east and 1 square south, a diagonal of about 206 miles.
• D. Millford to Dunmore: 2 squares east and 1 square south, a diagonal of about 112 miles.

The correct answer is A.

Tip: for a diagonal distance, the straight line is longer than either the east–west or the north–south part alone. Use the Pythagorean theorem (or compare the line with the scale bar) instead of counting squares only one way.

Test the claim against the driest counties (less than 10 inches): Ash (5 people per square mile), Elm (4), and Fenn (100).

Ash and Elm fit the claim. Fenn does not: it is in the driest category but has 100 people per square mile, more than every other inland county (Cedar has 60).

Why Fenn is different: the map shows the Silver River flowing through Fenn, and the table says its main activity is irrigated vegetables and cotton. River water replaces the missing rain.

The correct answer is C. It names the exception and explains it with evidence from both sources.

Why not the others? A and B support the claim instead of weakening it. D names a wet county with many people, which does not test what happens when rainfall is low. A claim that says "always" is weakened only by a case where the condition (low rain) is present but the result (few people) is not.

Tip: to weaken an "always" claim, look for a counterexample: the condition is true but the expected result is not.

Source 1's argument: farming on the dry plains is limited by "the water in the streams," so farms should be laid out so that each one reaches a stream.

How Source 2 challenges it: paragraph 2 says pumps and center-pivot sprinklers "allowed farmers far from any stream" to farm. Groundwater from the aquifer let farming spread beyond the streams, something the surveyor did not foresee.

How Source 2 supports it: paragraph 3 says the aquifer "refills very slowly," water is pumped "much faster than nature replaces it," and some wells have gone dry. Water is still the limit, just as the surveyor argued.

The correct answer is A.

Why not the others? B ignores the challenge: farmers clearly did farm far from streams. C overstates: Source 2 shows the water is running short, so the surveyor was not "completely wrong." D reverses the timeline and invents a claim: Source 2 never says rain increased.

Tip: "both challenge and support" questions want a balanced answer. Look for the choice with two halves, each tied to a different detail of the second source.

Apply the Ralo River evidence to the new river.

What the Ralo data show after the dam:

• silt reaching the delta: 85 → 9 million tons a year;
• shoreline lost to the sea: 2 → 30 feet a year;
• fish catch near the mouth: 18,000 → 4,500 tons a year;
• fertilizer used downstream: 5,000 → 42,000 tons a year.

Reasoning: A delta with fishing villages and rice farms depends on exactly what the Ralo delta lost: silt, nutrients, and stable land. The best-supported concern is that the delta could shrink and fish catches could fall, hurting both villages and farms.

The correct answer is D.

Why not the others? A contradicts the data: floods downstream fell from 6 to 1 per ten years. B contradicts the data: the Ralo dam produced 2,100 million kilowatt-hours a year. C contradicts the data: irrigated farmland grew from 120,000 to 310,000 acres. Each of these is a benefit of the Ralo dam, so it cannot be the best-supported concern.

Tip: on "apply to a new situation" questions, match the new place's features (fishing, delta farming) to the evidence from the known case, and choose the effect the evidence actually shows.