JAMB UTME - Geography - 2024

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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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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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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 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 ocean that connects Europe and America is the Atlantic Ocean.

Here's a simple explanation: The Atlantic Ocean is a massive body of water that lies between the continents of Europe and Africa to the east and the Americas to the west. This ocean is one of the world's five major oceans and is the second largest after the Pacific Ocean. Historically, the Atlantic Ocean has been significantly important as a route for ships traveling between Europe and the Americas, playing a crucial role in exploration, commerce, and cultural exchanges.

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Population density refers to the number of people living per unit of area, typically measured in people per square kilometer. In Nigeria, several factors influence population density, including natural, economic, and social factors.

Thick forest vegetation can influence population density by limiting the availability of land for habitation and agricultural activities. Areas with dense forests are usually less populated because they are harder to clear for settlements and farming. Additionally, thick forests may not have sufficient infrastructure, making them less attractive for people to live in.

Similarly, tsetse fly infestation can significantly influence population density. The tsetse fly transmits sleeping sickness, which can be a health hazard for humans and animals. Areas infested with tsetse flies might have lower population densities because people avoid settling in regions where their health and that of their livestock are at risk.

Fertile agricultural land attracts people because it supports farming activities, which is a primary livelihood for many people in Nigeria. As a result, such areas often have higher population densities due to the economic opportunities they provide.

The factor that least influences population density among the given options is mining. While mining can attract workers to specific areas, its influence is usually limited to certain regions where mineral resources are available. Since mining is typically localized and not widespread, its impact on overall population density is generally lower compared to factors like agriculture or disease. Additionally, mining areas might not have sustainable living conditions to attract large populations permanently.

In summary, while all these factors can influence population density, mining has the least impact compared to the other options because it affects fewer regions and often does not provide long-term settlement opportunities.

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The longest river in Africa is the Nile River. The Nile River is renowned for its extraordinary length, stretching approximately 6,650 kilometers (about 4,130 miles). This majestic river traverses several countries in northeastern Africa, including Uganda, Sudan, and primarily Egypt. Its extensive reach makes it the longest river not only in Africa but also in the world, although there is some debate with the Amazon River.

The Nile plays a crucial role in the cultures and economies of the nations it flows through. In ancient Egypt, for instance, it was vital for agriculture, enabling civilizations to thrive by providing a reliable source of water and fertile land for farming. Today, the Nile continues to be a lifeline for millions of people, supporting agriculture, transport, and providing drinking water.

In contrast, the other rivers mentioned, such as the Zambezi, Senegal, and Congo, though significant in their own right, are shorter and do not match the extraordinary length of the Nile River.

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The line of latitude that divides the Earth into two hemispheres is the Equator. The Equator is an imaginary line that is drawn around the middle of the Earth. It is equidistant from the North and South Poles, and it is located at 0 degrees latitude.

Because it sits exactly halfway between the poles, the Equator splits the Earth into two equal parts: the Northern Hemisphere and the Southern Hemisphere. The land and water areas located to the north of the Equator make up the Northern Hemisphere, while those located to the south comprise the Southern Hemisphere.

The importance of the Equator is not just in the division of hemispheres; it also plays a crucial role in climate. Regions located near the Equator typically experience a tropical climate with minimal temperature variations year-round.

In contrast, lines like the Tropic of Cancer and the Tropic of Capricorn are found north and south of the Equator, respectively, and they define the limits of the tropical zone. The Antarctic Circle is situated further south and marks a different climatic boundary.

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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.

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Rain clouds most commonly develop in the troposphere. The troposphere is the lowest layer of Earth's atmosphere and extends from the Earth's surface up to about 8 to 15 kilometers (5 to 9 miles) above sea level, depending on your location.

This layer is where we experience weather, including rain, thunderstorms, and clouds. The reason for this is that the troposphere contains most of the atmosphere's water vapor, which is essential for cloud formation and precipitation.

In this layer, the air becomes cooler as you go higher, which allows the moist air to rise, cool, and condense to form clouds. When these clouds get heavy enough with condensed water droplets, they release the water in the form of rain.

The layers above the troposphere, such as the stratosphere, do not usually have the right conditions for rain cloud formation because they lack sufficient moisture and their temperatures are not typically conducive to the processes needed for cloud formation.

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One characteristic that distinguishes urban settlements from rural settlements is that urban settlements are areas of secondary and tertiary activities.

Let's break this down:

• Urban Settlements: These are typically characterized by higher population density and more developed infrastructure. The economic activities here are primarily focused on secondary activities, such as manufacturing and industry, and tertiary activities, such as services like banking, education, healthcare, and retail. These activities are associated with more advanced stages of economic development and are common in cities and larger towns.


• Rural Settlements: On the other hand, rural areas are often associated with primary activities, such as agriculture, fishing, forestry, and mining. These activities involve direct extraction or harvesting of natural resources and are more common in less densely populated areas like villages or countryside.

To summarize, the primary distinction is that urban settlements focus on secondary and tertiary activities, providing goods and services, ultimately making them different in function and character from rural settlements, which focus more on primary activities.

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Coal is associated with organically-formed sedimentary rocks.

To understand why coal is associated with this type of rock, let's break it down:

1. **Sedimentary Rocks:** These rocks are formed from particles or sediments that accumulate and consolidate over time. Sedimentary rocks can be broken down further into different types based on their origins.

2. **Organically-formed Sedimentary Rocks:** This subgroup specifically forms from the accumulation of organic material, including plants and animals. Over millions of years, the remains of plants (especially those from swampy or wetland areas) accumulate in layers. As more and more layers build up, the pressure and heat from above cause these plant materials to transform into coal. Thus, coal is formed over long geological periods, through the compression of organic plant material.

This process differentiates organically-formed sedimentary rocks from mechanically-formed sedimentary rocks, which result from the mechanical process of weathering and erosion of existing rocks, and from igneous rocks like plutonic, which form from the solidification of magma, and crystalline rocks, which are typically associated with metamorphic processes. Thus, **coal is uniquely tied to organically-formed sedimentary rocks because of its plant-based origin**.

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The innermost section of the Earth is the core. The Earth is composed of several layers, starting from the surface and moving inward. These layers, from the outside to the inside, are the crust, mantle, outer core, and inner core.

1. Crust: This is the outermost layer of the Earth. It is very thin compared to the other layers and is where we live. The crust is made up of solid rocks and minerals.

2. Mantle: Located beneath the crust, the mantle is composed of semi-solid rock that flows slowly. It is the largest layer of the Earth by volume.

3. Core: The core itself is divided into two parts: the outer core and the inner core. The outer core is made of molten, liquid metal, while the inner core is made of solid metal, primarily iron and nickel. The core is the hottest section of the Earth, with extremely high temperatures and pressures. It is situated at the center of the Earth and provides heat that helps power the movement of tectonic plates and causes volcanic activity.

Therefore, when we refer to the innermost section of the Earth, we are specifically talking about the core, and more accurately, the inner core.

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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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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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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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Mercury and Venus are the two planets that lie between the Sun and Earth.

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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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The port described in the statement is an entrepôt. An entrepôt is a type of port or a trading post where goods are imported, stored, and then re-exported. It acts as a key transfer point in international trade, allowing products to be redistributed to neighboring countries. This concept operates on the idea that items arrive in bulk and then are sent out again, perhaps even modified or repackaged, often without the goods being subject to customs duties. In essence, an entrepôt streamlines the movement of goods, facilitating international commerce and boosting trade networks.

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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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Mining in Africa faces several challenges, but understanding these issues helps in realizing the unique dynamics of the industry on the continent.

Inadequate Unskilled Labour: This is generally not a problem in Africa. The continent has a large population that provides sufficient unskilled labor for mining activities. Thus, an abundance of unskilled labor makes this factor not a significant issue for mining operations.

Use of Obsolete Technology: Many mining operations in Africa struggle with outdated or insufficient technology. This affects the efficiency and safety of mining activities, making it a significant challenge for the industry.

Shortage of Power: Power shortages are common in many African countries and can severely impact mining operations, which require consistent and significant energy for their activities. This is a critical challenge in mining across the continent.

Inadequate Foreign Capital: Many African nations experience difficulty in attracting sufficient foreign capital to invest in modernizing and expanding their mining sectors. This capital is crucial for technology upgrades and infrastructural development in the industry.

In summary, inadequate unskilled labour is not typically a problem for mining in Africa, whereas the other issues listed are significant challenges impacting the industry.

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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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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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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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A **coastal plain** is a **large expanse of low, level land** that is formed due to an **uplift of part of the sea floor bordering a continent**. Essentially, it is an area where the land is relatively flat and is located near the coast.

This type of landform often occurs due to geological activities over time where the sea floor is pushed upwards, resulting in a broad, flat land surface extending inland from the coast. Coastal plains are typically characterized by their flat terrain and proximity to the ocean, making them influenced by marine conditions.

In summary, **a coastal plain is the result of the elevation of a portion of the sea floor adjacent to the continent**. It is characterized by its flatness and location near the sea, distinguishing it from other types of plains such as deltaic, outwash, or flood plains which have different formation processes and characteristics.

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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 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 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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To determine which of the listed items is not an element of climate, we need to understand what elements constitute climate. **Climate** refers to the average weather conditions of a place over a long period, typically 30 years or more. The primary elements that define climate include **temperature**, **precipitation**, **humidity**, **wind**, and **air pressure**. Let's go through the choices given:

Precipitation: This is an important element of climate as it refers to any form of moisture that falls from the atmosphere to the earth's surface, such as rain, snow, or sleet.

Air pressure: This is a crucial element of climate because it influences wind patterns and weather systems such as cyclones and anticyclones.

Altitude: This is not an element of climate; rather, it is a geographic factor that influences climate. As you go higher in altitude, temperatures typically decrease, which can affect the climate of a region, but altitude itself is not a climatic element.

Temperature: This is a fundamental element of climate, affecting the average warmth or coldness of a place over time.

Therefore, **altitude** is not an element of climate, but a factor that can influence the other elements like **temperature** and **precipitation**.

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A mercury barometer is used for measuring atmospheric pressure.

Here's a simple explanation:

A barometer is an instrument designed to measure the pressure exerted by the atmosphere. The atmosphere exerts pressure because of the mass of air above the Earth, and this pressure changes as you move up and down in altitude or due to weather systems.

A mercury barometer consists of a long glass tube closed at one end and filled with mercury. The open end of the tube is placed in a bowl of mercury, called a reservoir. The pressure from the air pushing down on the mercury in the bowl forces the mercury up the tube. When the atmospheric pressure is high, the mercury in the tube rises, and when the atmospheric pressure is low, the mercury level falls.

Thus, by measuring the height of the mercury column in the tube, we can determine the atmospheric pressure. In summary, a mercury barometer provides a way to directly observe changes in the atmospheric pressure.

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The Economic Community of West African States (ECOWAS) is a regional political and economic union of countries located in West Africa. Its objective is to promote economic integration across the region. The official member states of ECOWAS include countries in West Africa.

Among the options provided:

• Cote d'Ivoire is a member of ECOWAS. It is located in West Africa and actively participates in the community’s activities.
• Burkina Faso is also a member of ECOWAS. Like Cote d'Ivoire, it is found in West Africa and is part of the union.
• Senegal is another member state of ECOWAS, contributing to the regional integration efforts.

Cameroun, however, is not a member of ECOWAS. While it is geographically close to West Africa, it is primarily considered part of Central Africa, and it is a member of the Central African community organization instead.

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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 activity that requires a large area of land usually in thousands of hectares, availability of water either in the form of rain or irrigation, and a high capital outlay is plantation agriculture. Let me explain why:

Large Area of Land: Plantation agriculture involves the cultivation of crops on a very large scale, often requiring thousands of hectares. This is necessary to achieve economies of scale and produce significant quantities of a specific crop such as tea, coffee, sugarcane, rubber, or oil palm.

Availability of Water: Crops grown on plantations need adequate water supply to thrive. This can be provided by regular rainfall or through irrigation systems. Thus, plantations are often located in regions with favorable climatic conditions or equipped with efficient water management systems.

High Capital Outlay: Establishing a plantation requires a significant initial investment. This includes procuring land and machinery, setting up irrigation systems, and maintaining infrastructure. Furthermore, plantations often rely on the employment of many workers and the use of advanced agricultural techniques, which also contribute to the high cost.

In contrast, the other activities mentioned do not primarily rely on these three factors to the same extent. For example, lumbering involves harvesting trees, which may also require substantial land area, but does not necessarily need irrigation. Tourism industry might require watering systems for landscaping, but its focus is more on site attractions. Finally, while mining requires high capital outlay and can cover large areas of land, it does not depend on the availability of irrigation systems like plantation agriculture does.

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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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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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To determine which option is not a proof of the Earth's spherical shape, let's examine each one:

Twilight and Dawn: Twilight and dawn occur when the Earth rotates, and the sun is below the horizon. The gradual increase or decrease in light during these times is due to the atmosphere bending or scattering sunlight. While this phenomenon is observed worldwide, it by itself doesn't directly indicate a spherical Earth. Instead, it emphasizes the Earth's rotation, which is consistent with a spherical shape.

Lunar Eclipse: During a lunar eclipse, when the Earth is directly between the sun and the moon, the Earth casts a shadow on the moon. This shadow is observed as a circular shape, which provides direct evidence that the Earth is spherical.

Aerial Photograph: Aerial photographs, when taken from a sufficient altitude, can show the curvature of the Earth. Photographs taken from high altitudes give visual evidence of the Earth's curved surface, supporting the spherical shape.

Sunrise and Sunset: The occurrence of sunrise and sunset happens due to the Earth's rotation on its axis. As the Earth rotates, different parts of the world experience sunlight and darkness. This rotation is consistent with the global experience of a spherical planet.

Conclusion: While all the listed phenomena have some connection to the Earth's rotation and shape, **twilight and dawn** do not directly serve as a proof of the Earth's spherical shape. They are more indicative of the rotational aspect and atmospheric effects rather than the shape itself.

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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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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 ancient Greeks were pioneers in observing and classifying the Earth's climate zones. They recognized three primary climatic belts based on their understanding of the Earth's environment. These belts were:

• Torrid Zone: This zone is the hottest part of the Earth, located near the equator. The Greeks believed it to be extremely warm because it lies where the sunlight strikes the Earth most directly. Today, we know this region as the tropical zone.
• Temperate Zone: This area lies between the torrid and frigid zones. It experiences more moderate temperatures. The Greeks saw this as a **habitable** zone, with a climate suitable for a majority of human living. It corresponds to the mid-latitudes in modern geography.
• Frigid Zone: This is the coldest area, positioned around the poles. The Greeks considered it extremely cold and largely uninhabitable due to its distance from the equator and the angle at which sunlight reaches these regions. Today, this relates to the polar regions.

Thus, the Greeks recognized these **three climatic belts**: Torrid, Temperate, and Frigid. This classification was an early attempt to systematically understand the Earth's climatic patterns using observable natural phenomena, such as sunlight and temperature differences.

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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.