JAMB UTME - Geography - 2024

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When wet and dry bulb thermometers, which together form a psychrometer, record the same temperature, it indicates that the air is saturated. This means that the air has reached its maximum capacity to hold water vapor, also known as reaching the dew point.

Normally, the wet bulb thermometer, which has a cloth soaked in water wrapped around it, shows a lower temperature than the dry bulb thermometer because evaporation cools it down. However, when the temperatures are the same for both thermometers, no evaporation is taking place. This is because the air cannot accept more water vapor, pointing to a humidity level of 100%, which is known as saturation.

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The **Horn of Africa** is a prominent peninsula in East Africa that juts into the Arabian Sea. It consists primarily of four countries: **Ethiopia**, **Eritrea**, **Somalia**, and **Djibouti**. From the options provided, only **Djibouti** is located within the Horn of Africa. This makes Djibouti geographically significant in terms of its positioning in this specific region.

For further understanding, here is a brief description of the other countries mentioned:

• Kenya: Although located in East Africa, it is situated below Ethiopia and does not form part of the Horn of Africa.
• Chad: This country is located in Central Africa and is far away from the Horn of Africa.
• Swaziland (now called Eswatini): This is a landlocked country in Southern Africa, nowhere near the Horn of Africa.

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On June 21st, the sun is overhead at the Tropic of Cancer, marking the Summer Solstice in the Northern Hemisphere. This is the point in the year when the Northern Hemisphere is tilted closest to the sun. As a result, places in the Northern Hemisphere experience their longest day and shortest night. This means that there is more daylight compared to nighttime.

To summarize, on this date, locations in the Northern Hemisphere will experience a longer day and a shorter night. This is due to the tilt of the Earth's axis, which maximizes sunlight exposure to these regions.

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One of the major problems in agricultural development in Nigeria is the insufficient storage facilities.

The agricultural sector in Nigeria often faces difficulties after crops are harvested. Poor storage facilities mean that a substantial portion of the agricultural produce is lost due to spoilage, pests, or damage. This is a significant challenge because:

• **Loss of Produce:** Without adequate storage, farmers cannot preserve excess produce for future use, which leads to food waste and instability in food supply.
• **Reduced Income:** When farmers are unable to store their produce, they may have to sell it quickly and often at lower prices, immediately after harvest. This reduces their potential earnings.
• **Market Imbalance:** Lack of storage facilities can lead to an overflow of produce in the market right after harvest and a shortage during off-season periods, causing fluctuating prices.
• **Quality Degradation:** Poor storage facilities can lead to the degradation of the quality of produce, which in turn affects marketability and consumer trust.

Improving storage facilities would provide farmers with the ability to manage their production better, ensuring a more consistent supply of agricultural products and contributing significantly to the development of agriculture in Nigeria.

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There is no such thing as a "mountain of accumulation". The other options - conical mountain, block mountain, and fold mountain - are all types of mountains.

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On 22nd December, the sun is directly overhead the Tropic of Capricorn in the Southern Hemisphere. This marks a significant event in both hemispheres.

In the Northern Hemisphere, this date corresponds to the **winter solstice**. Here's why:

The Earth is tilted on its axis by about 23.5 degrees. This tilt is responsible for the changing seasons. Throughout the year, different parts of the Earth receive varying amounts of sunlight depending on the planet's position in its orbit around the Sun.

During the winter solstice, the Northern Hemisphere is tilted farthest away from the Sun. As a result, it experiences the shortest day and the longest night of the year. The **winter solstice** marks the official start of winter in the Northern Hemisphere.

Thus, when the sun is directly overhead at the Tropic of Capricorn on 22nd December, the Northern Hemisphere experiences its **winter solstice**.

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Rocks that are formed from the cooling and solidification of molten magma are called igneous rocks.

To put it simply, when rocks melt deep beneath the Earth's surface because of the high temperatures, they turn into a liquid called magma. This magma can sometimes rise to the surface in the form of lava. Once either the magma or lava cools down and becomes solid, it forms a new type of rock known as igneous rock.

These rocks can be formed inside the Earth when the magma cools slowly, creating large crystals, or on the Earth's surface, when the lava cools quickly, often resulting in smaller crystals. The word "igneous" comes from a Latin word meaning "fire," which appropriately describes how these rocks form from the hot, molten magma.

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The major source of power for most terrestrial ecosystems is solar energy.

Let me explain why:

Solar energy is the energy that comes from the sun. It is critical for life on Earth as it powers the process of photosynthesis, which is used by plants, algae, and some bacteria to convert light energy into chemical energy. During photosynthesis, these organisms take in carbon dioxide from the air and water from the soil, and with the help of sunlight, they produce glucose and oxygen. This process provides the necessary energy and organic material to support life.

Here is why it is important:

• Primary Producers: Solar energy fuels the primary producers (mainly plants) that form the base of the food chain. They use sunlight to create food that herbivores eat, and these herbivores are then consumed by carnivores. Without the energy provided by the sun, this foundational level of the food web would not exist, and all life forms that depend on plants, either directly or indirectly, would not survive.
• Energy Transfer: The energy captured by plants is transferred through various trophic levels as different organisms consume one another. Each level receives energy that originated from the sun, making solar energy the primary driving force of energy flow in ecosystems.
• Climate Regulation: Sunlight helps regulate Earth's climate and atmospheric conditions, influencing temperature and weather patterns. These conditions are necessary for the survival of various ecosystems and their inhabitants.

In comparison, other energy sources like geothermal energy, nuclear power, and hydroelectric power play relatively minor roles in terrestrial ecosystems. These energies are not as directly involved in powering the basic life-sustaining processes as solar energy is. Therefore, it is clear that solar energy is the predominant power source for life on land.

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The term over-population is best defined as the situation where the population exceeds available resources. This means that the number of people in an area is greater than the resources available to sustain them, such as food, water, shelter, and health care. It can lead to various problems including poverty, environmental degradation, and a strain on infrastructure. Over-population occurs when the existing resources cannot meet the needs of the people, resulting in hardship and reduced quality of life.

In contrast, having a birth rate equal to the death rate implies a stable population over time, not necessarily over-population. Increasing birth rate and decreasing infant mortality can contribute to population growth, but they do not solely define over-population. Finally, high population density refers to a large number of people living in a small area, which could lead to over-population if resources are insufficient, but high density alone does not equate to over-population.

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The environmental hazard that is due primarily to human activities is ozone depletion.

The ozone layer is a protective shield in the Earth's stratosphere that absorbs most of the Sun's harmful ultraviolet radiation. The thinning of the ozone layer is mainly caused by the release of man-made chemicals. The most significant contributors to this environmental hazard are chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS) which have been used in refrigeration, air conditioning, foam production, and aerosol propellants. When these chemicals reach the stratosphere, they break down ozone molecules, leading to what is known as the "ozone hole."

In contrast, the other environmental hazards listed—hurricanes, earthquakes, and volcanic eruptions—are natural phenomena. While human activities can influence the severity or impact of these events, such as through climate change exacerbating the intensity of hurricanes or human settlement in earthquake-prone areas, they are not primarily caused by human actions.

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The high population density in the Nile Valley is best explained by the presence of rich alluvial soil. The Nile River floods annually, depositing nutrient-rich silt along its banks, which creates fertile land perfect for agriculture. This fertile land supports farming, which is the primary means of livelihood for many people in the region. The availability of fertile soil allows for the cultivation of crops such as wheat, barley, and other foodstuffs, supporting a large population by providing food resources and encouraging human settlement. This agricultural productivity attracts people to settle, leading to a higher population density. It is not primarily due to climate, migration from Europe, or oil fields.

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An example of an organically formed sedimentary rock is coal.

Coal is formed from the remains of dead plants that accumulated in ancient swamps and wetlands. Over millions of years, these plant materials were buried under layers of sediment. As more layers built up on top, the increased pressure and heat transformed the plant remains into coal. The process involved is known as biochemical sedimentation, where organic materials are compacted and altered to form rock.

This is in contrast to the other options:

• Granite is an igneous rock, not sedimentary, formed from cooled magma or lava.
• Rock salt is a chemical sedimentary rock formed when water evaporates, leaving behind salt crystals.
• Sandstone is a clastic sedimentary rock formed from compacted sand particles.

To summarize, coal is the organically formed sedimentary rock among these options because it originates from ancient plant material that has undergone compaction and chemical transformation over time.

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A great advantage of Basin irrigation is that water is not wasted, as the basin helps to trap and conserve water.

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Sills, dykes, and batholiths are examples of intrusive volcanic landforms. These are geological formations that are created below the Earth's surface from cooled and solidified magma.

Here's a simple explanation of each:

Sills are formed when magma intrudes between pre-existing layers of rock, creating a horizontal or near-horizontal sheet of solid rock. Over time, they cool and solidify, forming a flat or gently undulating body of igneous rock parallel to the layers it intruded.

Dykes occur when magma cuts across pre-existing rock layers, forming a vertical or steeply inclined body of rock. They act as pathways for magma movement and can be seen as wall-like structures that cut through layers of surrounding rock.

Batholiths are massive formations created when large amounts of magma slowly cool and solidify deep beneath the Earth's surface over a long period. These large rock bodies can cover thousands of square kilometers and are often exposed at the surface after extensive erosion.

All of these formations are created through the intrusion of magma into existing rock. As a result, they are classified as intrusive volcanic landforms, due to their origin beneath the Earth's surface, in contrast to extrusive volcanic landforms formed by lava cooling on the surface.

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When a ship appears over the distant horizon, the mast is seen before the hull. This phenomenon can be explained by considering the shape of the Earth and how light travels.

The Earth is a large sphere, and because of its curvature, objects that are farther away become obscured by the Earth's surface as they move over the horizon. The upper parts of an object, such as the mast of a ship, are further away from the Earth's surface compared to the lower parts, like the hull. As a result, the top parts become visible first as an object like a ship comes over the horizon.

Therefore, due to the curvature of the Earth, the mast, being higher and more elevated, comes into view before the hull as the ship approaches from a distance.

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Let's understand the term **headward erosion**. **Headward erosion** refers to the process where a river or stream erodes its source region, causing the stream's origin to move backward away from the direction of water flow. This process can have several impacts and can lead to the formation of certain landforms.

Among the options provided, **headward erosion** is most commonly associated with the formation of **river capture**. When **headward erosion** continues over time, it can cause one river to extend its course and intersect with a neighboring river, capturing its flow. This event is known as **river capture** or **stream piracy**. Essentially, the rapid erosion at the river's source enables it to cut through the drainage divide and capture the headwaters of another river.

Let's briefly see why the other options are less relevant to **headward erosion**:

• **Potholes** are typically formed on the riverbed as a result of mechanical weathering and the swirling movement of water and debris, rather than headward erosion.
• **Oxbow lakes** form when a meander from a river is cut off, creating a free-standing body of water, which is more a result of lateral erosion rather than headward erosion.
• **Alluvial cones** or **alluvial fans** form where a river or stream spreads out sediment as it exits a mountainous area onto a flatter plain. This is not directly caused by **headward erosion**, but rather sediment deposition.

Therefore, the process of **headward erosion** most directly leads to the formation of **river capture**.

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The **most common mode of transportation in Africa** is **road transportation**. This includes vehicles like cars, buses, and motorcycles that travel on roads and highways. Road transportation is widespread because it is **versatile** and can reach many rural and urban areas that are not accessible by other means of transportation. Roads are often less expensive to build and maintain compared to infrastructure needed for other modes such as railways or airports.

Despite the challenges such as limited road networks and varying road conditions in some regions, **road transportation remains the backbone** of both passenger and freight transport due to its **flexibility** and **accessibility**. In many African countries, it is the most relied upon form of transport connecting people to markets, healthcare facilities, schools, and places of employment.

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Rural-urban migration refers to the movement of people from rural areas to urban areas in search of better opportunities and living conditions. One of the main effects of this kind of migration is rural depopulation.

Here's why:

• Rural Depopulation: When significant numbers of individuals leave the rural areas for urban centers, the population in these rural areas declines. This is because more people are exiting than entering these areas. As a result, the overall population density decreases.


• Rural Unemployment: Paradoxically, rural unemployment might decrease rather than increase. This is because those who migrate are often people who were already unemployed or underemployed and looking for better job opportunities. When they leave, the unemployment rate in the rural area may stabilize or even decrease because the remaining population might have more employment opportunities.


• Rural Congestion: Is not an effect of rural-urban migration. In fact, with fewer people, congestion in rural areas typically diminishes.


• Urban Depopulation: When people migrate from rural areas to urban areas, the urban areas' population increases while the rural areas' population decreases. Hence, urban depopulation is not applicable in this context.

In summary, rural depopulation is one of the primary effects of rural-urban migration as it results in a decrease in the population of the rural areas being vacated.

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The geographical region of Nigeria described in the question is the North-Central Highlands. This area covers about one-fifth of the country and is characterized by a generally flat surface with granitic hills, known as inselbergs, scattered throughout the landscape. These hills are composed of hard rock formations that have resisted erosion, thereby standing out from the flatter surroundings.

This region is situated in the north-central part of Nigeria and is significant for its geological features and agricultural potential. The flat terrain provides an expansive area suitable for farming, while the inselbergs add to the region's natural beauty and sometimes serve as landmarks. The North-Central Highlands are an important and distinct geographical region within Nigeria due to these unique characteristics.

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The climatic type found on the western margins of continents between latitudes 30° and 40° North and South of the Equator is the Mediterranean climate.

The Mediterranean climate is characterized by its unique seasonal weather pattern:

• Hot, dry summers: During the summer months, these regions usually experience clear skies, ample sunshine, and little to no rainfall. The temperatures are generally high due to the influence of the subtropical high-pressure systems.
• Mild, wet winters: In the winter months, these areas receive moderate rainfall, often brought by westerly winds and cyclonic storms, while temperatures remain relatively mild and comfortable.

This type of climate is well-known for supporting specific kinds of ecosystems and is suitable for growing certain crops, such as olives, grapes, and wheat. Typical regions with a Mediterranean climate include the coastal areas of the Mediterranean Sea, parts of California in the United States, central Chile, the southern tip of South Africa, and southwestern Australia.

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The movement of population from rural areas to cities, commonly known as urbanization, is influenced by several factors, particularly economic and social opportunities. In the context of Nigeria, one of the most significant reasons is due to the availability of more job opportunities in the cities. Urban centers often offer a greater variety of employment possibilities compared to rural areas. These opportunities can be in industries, services, or various sectors requiring skilled and unskilled labor.

Economic development tends to be concentrated in cities, attracting individuals seeking better employment prospects and higher income potential. Many people move to urban areas in search of work that they cannot find in their rural hometowns, where agriculture may be the predominant source of livelihood with limited economic diversification.

Moreover, cities in Nigeria typically provide better recreational facilities and services than rural areas. These include access to modern amenities such as shopping centers, cinemas, sports facilities, and cultural events, which contribute to a higher quality of life. This aspect is appealing, particularly to younger generations, creating an added incentive for migration.

The other factors mentioned, such as food scarcity in rural areas, might contribute to migration but are often secondary compared to the employment factor. Many rural areas have agricultural activities, so food scarcity is not the primary reason; instead, it's the lack of economic opportunities that often triggers the movement.

Finally, while it is true that the cost of living in the cities is very high, especially in terms of housing and services, this is not a reason that attracts people to move. In fact, it might be a deterrent. Nonetheless, the potential for better income and lifestyle improvement in cities often outweighs the high cost of living for many migrants.

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The angular distance of a point on the Earth's surface measured in degrees from the centre of the Earth east or west of the Greenwich Meridian is known as longitude.

Let's break this down to make it simple:

Longitude lines are imaginary lines that run from the North Pole to the South Pole. The most important line is the Greenwich Meridian, also called the Prime Meridian, which is the reference point for measuring longitude. It is designated as zero degrees (0°) longitude. When you measure how far east or west a point is from the Prime Meridian, you are measuring the longitude.

This is different from latitude, which measures the distance north or south of the Equator. Longitude lines meet at the poles, whereas latitude lines are parallel to each other.

Overall, longitude helps us determine the precise location of a place on Earth by specifying how far east or west it is from the Prime Meridian.

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Life expectancy refers to the average age at which people die. It is a statistical measure that estimates the average number of years a person is expected to live based on current mortality rates. Life expectancy can vary significantly based on various factors such as geography, lifestyle, healthcare quality, and socioeconomic status. It serves as an important indicator of a population's overall health and quality of life.

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The bush fallowing system in West Africa is not very economical in the use of land. Bush fallowing involves leaving land fallow for several years to regain its fertility, which can lead to inefficient use of land.

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One of the major problems impacting the effective utilization of human resources in West Africa is unemployment.

Unemployment is a significant issue because it leads to several challenges that adversely affect both individuals and the economy at large. When people, especially those who are capable and willing to work, do not have jobs, it results in a waste of potential human resources. Let's break down a few reasons why unemployment is such a pressing problem:

• Economic Impact: High unemployment rates mean that a large portion of the population is not contributing to the economic growth of the country. This diminishes the overall productivity and can lead to a lower Gross Domestic Product (GDP).
• Poverty: Unemployment often results in income instability, which can push individuals and families into poverty. This lack of income makes it challenging to meet basic needs such as food, education, and healthcare.
• Social Challenges: High levels of unemployment can lead to increased crime rates and social unrest, as people without jobs may resort to illegal activities to support themselves.
• Brain Drain: Persistently high unemployment can lead to emigration, where skilled individuals move to other countries in search of better opportunities. This exacerbates the issue as it creates a loss of talented individuals who could have contributed to local development.
• Skill Deterioration: When people remain unemployed for extended periods, their professional skills may deteriorate, making it even harder for them to find employment in the future.

Addressing unemployment requires collaborative efforts involving government policies, education systems, and private sector initiatives to create more job opportunities and develop skills that match the demands of the labor market. Therefore, unemployment remains a critical concern in achieving optimal utilization of human resources in West Africa.

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The outer layer of the Earth is called the crust. Let's understand this in simple terms:

The Earth is made up of several layers. Imagine the Earth like an onion with different layers, with each layer varying in composition and physical properties. The outermost of these layers is the crust.

The crust is similar to a thin shell around the Earth. It is very thin compared to the other layers and can be thought of as the Earth's skin. It is made up of solid rocks and minerals and is where we live and see landscapes, mountains, and oceans.

Below the crust is the mantle, which is much thicker and composed primarily of semi-solid rock. Therefore, when talking about the outermost layer, we refer specifically to the Earth's crust.

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The solar system is a vast and fascinating system that centers around the Sun, a star that provides light and heat to all the celestial bodies that revolve around it. Understanding what other components make up the solar system is essential for grasping how our cosmic neighborhood operates.

There are eight major planets that orbit around the Sun. These planets, in their order from the closest to the farthest from the Sun, are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Each of these planets varies in size, composition, and distance from the Sun, but they all follow elliptical orbits.

In addition to the eight recognized planets, there are also dwarf planets, such as Pluto. Pluto was previously considered the ninth planet until it was reclassified as a dwarf planet by the International Astronomical Union in 2006 due to updated criteria that define what constitutes a planet.

Besides planets and dwarf planets, the solar system also contains a variety of other celestial bodies. These include moons, which are natural satellites that orbit planets; asteroids, which are small rocky bodies primarily located in the asteroid belt between Mars and Jupiter; and comets, which are icy bodies that have eccentric orbits bringing them close to the Sun occasionally.

In summary, the solar system comprises the Sun and eight planets, alongside other celestial bodies such as dwarf planets, moons, asteroids, and comets. Understanding the composition of the solar system helps us appreciate the complexity and grandeur of our cosmic environment.

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The decline in the importance of rail transport in Africa can be best explained by the high competition from road transport. Here's why:

Accessibility and Flexibility: Road transport is generally more accessible and flexible compared to railways. Roads are available in most areas of Africa, including rural regions, allowing goods and passengers to reach their destinations directly without requiring transfer between modes of transport.

Cost-Effectiveness: In many cases, road transport can be more cost-effective because it eliminates the need for transferring goods at several points. The initial investment in road infrastructure and vehicles can also be less than maintaining or upgrading railway networks.

Adaptability to Infrastructure Limitations: Many railways in Africa suffer from outdated infrastructure, which can hinder their efficiency and reliability. On the other hand, road transport can easily adapt to newer roads and infrastructures as they are developed.

Length of Transport Routes: Although Africa is a vast continent, many trade routes within countries or regions are more economically feasible with road transport, especially for short to medium distances.

Overall, while other factors such as the low volume of goods and potential retrenchment threats exist, the dominance and rapid improvement in the road transport sector particularly highlight why rail transport has seen a decline in relevance. The flexibility and economic viability of road transport often make it a more attractive choice for businesses and individuals alike.

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The location of a cement factory is primarily influenced by its proximity to the source of raw materials. Cement production involves the use of abundant natural resources such as limestone, clay, and rock, which are crucial ingredients in the manufacturing process. These raw materials are usually heavy and bulky, making transportation costly. Therefore, by situating the cement factory near these resources, transportation costs can be minimized, leading to more efficient and cost-effective production. This proximity also ensures a steady and reliable supply of raw materials, which is essential for uninterrupted production.

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To determine the longitude of place X, we need to understand the relationship between time and longitude. The Earth is divided into 360 degrees of longitude, and it completes one full rotation (360 degrees) in 24 hours. Therefore, for every hour, the Earth rotates 15 degrees of longitude.

The given information is this:

• Greenwich Mean Time (GMT) is 5:00 a.m.
• Local time at place X is 12:00 noon.

The difference in time between GMT and the local time at place X is 7 hours (from 5:00 a.m. to 12:00 noon).

Calculation:

• For each hour, there is a 15-degree difference in longitude.
• Therefore, a 7-hour difference corresponds to 7 hours × 15 degrees/hour = 105 degrees.

Now, we need to determine whether place X is east or west of the Prime Meridian (0° longitude, the reference line for GMT).

- Since the local time at place X is ahead of GMT (12:00 noon compared to 5:00 a.m.), it means X is east of the Prime Meridian.

Thus, place X is located on 105°E.

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In terms of the largest timber producers in Africa, it is important to understand which nation has significant timber resources and an established forestry industry. Zaire, known today as the Democratic Republic of Congo (DRC), is recognized as the largest timber producer in Africa.

The Democratic Republic of Congo has extensive forest coverage, including parts of the Congo Basin, which is the second-largest rainforest in the world after the Amazon. This vast expanse of forestland provides an abundance of timber resources. The country's forestry industry has developed around this natural resource, contributing significantly to its economy.

Other countries like Ghana and Nigeria also have substantial forests and timber industries, but they do not match the scale of Zaire. Malawi, on the other hand, is less known for timber production compared to these countries.

In summary, considering its massive forest expanse and established timber industry, Zaire (the Democratic Republic of Congo) stands out as Africa's largest timber producer.

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The description in question refers to sedimentary rocks. These types of rocks are primarily formed through the accumulation of material, which can be particles derived from other rocks or the remains of dead plants and animals. Here is a simple breakdown:

• Formation Process: Over time, these particles and organic materials settle in layers, usually at the bottom of lakes, rivers, and oceans. They undergo a process called compression and cementation. This means the weight of the layers pressing down causes them to stick together and form solid rock.
• Composition: Sedimentary rocks are made up of materials like sand, silt, clay, and gravel. Additionally, they often contain fossils, which are the preserved remains or traces of ancient life.
• Characteristics: One can easily identify sedimentary rocks by their layered appearance. These layers or strata are often visible in cliffs and road cuts as different colors or textures.
• Examples: Common sedimentary rocks include limestone, sandstone, and shale.

Sedimentary rocks play a crucial role in our understanding of Earth's history. The layers can tell scientists a lot about the Earth's past environments, climate, and even the organisms that lived long ago.

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Mechanical weathering is the process of breaking down rocks into smaller pieces without changing their chemical composition. There are several causes of mechanical weathering, but not all processes that affect rocks are related to mechanical weathering.

The options listed include:

Temperature changes: This is a cause of mechanical weathering. When rocks are exposed to fluctuating temperatures, they expand when it's hot and contract when it's cold. Over time, these repeated expansions and contractions can cause the rocks to crack and break apart.

Frost action: Also known as freeze-thaw weathering, this is another form of mechanical weathering. Water can seep into cracks in the rocks, and as temperatures drop, the water freezes and expands. This expansion exerts pressure on the rock, gradually breaking it apart.

Alternate wetting and drying: This causes mechanical weathering by changing the volume of clay minerals found in some rocks. When these rocks get wet, the clay swells, and when dry, it contracts. This constant expansion and contraction lead to mechanical breakdown.

Rain action: This is not primarily a cause of mechanical weathering. While rain can contribute to weathering processes, such as chemical weathering where it reacts with minerals in rocks to form new compounds, its primary role in mechanical weathering is minimal compared to other factors.

Therefore, among the options provided, rain action is the one that is not a direct cause of mechanical weathering.

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The temperatures of adjacent coastlands are reduced when on-shore winds blow over cold currents primarily because the cold currents influence the temperature of the prevailing winds.

Here's how it works in simple terms:

When winds blow over the ocean surface, they pick up characteristics of the water beneath them. If these winds travel over a cold ocean current, the air they carry becomes cooler. As this cooler air moves onto the coastlands, it brings down the temperature of those areas. This is why coastlands experience reduced temperatures when on-shore winds carry the chill from cold ocean currents.

So, the key factor here is the cooling effect of the cold water, which cools the air above it, consequently lowering the temperature of the coastal regions the wind blows onto.

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The equatorial diameter of the earth is approximately 6,760 km. This is the distance from the equator to the equator, passing through the center of the earth.

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Wind action is more predominant in arid regions due to the combination of loose surface materials and the absence of vegetation cover. In these regions, there is little moisture to bind soil particles together, making them easily detachable and transportable by wind. Without vegetation to stabilize the soil and buffer wind, these loose particles are swept away, leading to significant wind erosion.

Other reasons, such as insufficient drainage or strong winds, also play a role; however, the **primary** factors are the loose surface materials and lack of vegetation, allowing wind to act with greater intensity. In contrast, humid regions have ample vegetation and soil moisture, which significantly reduce the wind's ability to erode and transport surface material.

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Copper is an important raw material in the electrical industry. This is because copper is an excellent conductor of electricity, which means it allows electrical current to flow through it easily with minimal resistance. This property makes copper ideal for use in electrical wiring, motors, transformers, and other electrical components. Additionally, copper is highly durable, resistant to corrosion, and versatile, which further enhances its usefulness in electrical applications. The electrical industry relies heavily on copper to ensure reliable and efficient power transmission.

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The part of the earth's crust that is covered by oceans and seas is called the hydrosphere.

Let's break it down logically:

• The hydrosphere specifically refers to all of the water found on, under, and over the surface of the Earth, including oceans, seas, rivers, lakes, and even water in the atmosphere.
• It covers about 71% of the Earth's surface, making it a significant and distinctive part of the planet.
• The stratosphere and the ionosphere are layers of the Earth's atmosphere, not related to water or Earth's crust coverage.
• The biosphere refers to all regions of the Earth occupied by living organisms. While it includes oceans and seas, it is not specific to just water coverage.

Therefore, the term that correctly describes the part of the Earth's crust covered by water bodies like oceans and seas is the hydrosphere.

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Hong Kong, Java, and Manhattan all share the feature of having a **high population density**. These regions are known for their concentrated population in relatively small areas. Here is a simple explanation for each:

• Hong Kong: As a major financial and cultural center, Hong Kong is known for its skyscrapers and bustling city life, housing a large number of people in a compact space.


• Java: This Indonesian island is one of the most densely populated places in the world, being the political, economic, and cultural hub of Indonesia.


• Manhattan: In New York City, Manhattan is famous for its urban density, with many people living and working in high-rise buildings within a small area, contributing to its status as a significant commercial and cultural center.

In summary, the common feature among these locations is their **high population density**, where large numbers of people reside and engage in various activities within limited geographic spaces.

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Nigeria, a country located in West Africa, is situated between the longitudes of 3°E and 15°E. Longitude lines are imaginary vertical lines that run across the Earth's surface from the North Pole to the South Pole. These lines help in determining the east-west position of a particular location on earth. By being positioned between 3°E and 15°E, Nigeria stretches from slightly east of the Prime Meridian, which is 0°, to 15° eastward. This geographical positioning affects several aspects like climate and time zone, making it an important detail in understanding the country's location globally.