JAMB UTME - Geography - 2024

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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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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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The route that is not a sea route is the one involving London, Moscow, and Baghdad.

Here's the explanation:

• The other listed routes such as New York-London-Rotterdam, London-Capetown-Melbourne, and Sydney-Suez-London primarily involve locations that are major port cities or are connected by significant sea passages, allowing ships to travel via water routes.
• On the other hand, Moscow is a landlocked city in Russia, and although it has some rivers, it does not have direct access to the sea. Moreover, the path from London to Moscow to Baghdad mostly travels overland, across Europe and parts of Asia, which are areas not typically traversed by ships in any well-known sea route.

This is why the route from London, Moscow, and Baghdad is not a sea route.

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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 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 **Gezira Scheme** and the **Manaquil Extension** are famous for the cultivation of **cotton**. These agricultural projects are located in **Sudan** and are among the largest irrigation projects in the world dedicated to agriculture.

The Gezira Scheme utilizes the waters of the **Blue Nile** to irrigate the land, making it suitable for growing cash crops. The scheme's infrastructure, including an extensive network of canals and ditches, supports the broad-scale cultivation of cotton. Similarly, the Manaquil Extension enhanced the irrigation reach, further bolstering cotton agriculture.

**Cotton** is highly suitable for growth in the hot climate of Sudan, especially under irrigation, as it requires a long growing season with plenty of sunshine and water. This makes it an ideal crop for the region, contributing significantly to Sudan's economy through both local use and export. Additionally, cotton plays a crucial role in the livelihood of many farmers in the region, being a major source of income.

Cultivating cotton in **Gezira** and **Manaquil** not only supports the textile industry but also generates employment for thousands of people engaged in farming, processing, and trade.

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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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A conurbation is a term used to describe a group of cities, towns, or urban areas that have merged together to form a single urban entity, while still retaining their individual identities.

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On June 21st, when the sun is overhead at the Tropic of Cancer, places in the Northern Hemisphere experience a phenomenon often referred to as the **Summer Solstice**. This day marks the point when the Northern Hemisphere is tilted closest to the Sun. As a result, it receives the most direct sunlight compared to any other day of the year.

During this time, the day is significantly longer than the night. This is because the Sun travels a longer path through the sky, remaining visible for a larger portion of the 24-hour day. Therefore, areas in the Northern Hemisphere experience a **longer day and shorter night**.

This occurrence is most noticeable the further north you go, with some regions near the Arctic Circle experiencing the phenomenon known as the "Midnight Sun," where the sun is visible at midnight.

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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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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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The term fossil fuel refers to energy sources that come from the remains of ancient plants and animals, buried and subjected to heat and pressure over millions of years. These fuels are primarily composed of carbon and include materials like coal, oil, and natural gas.

Among the options given:

• Gneiss is a type of metamorphic rock formed from other rocks like granite or sedimentary rock through heat and pressure. It is not a fossil fuel.
• Granite is an igneous rock that forms from the cooling and solidification of magma beneath the Earth’s surface. It is not a fossil fuel.
• Lignite is a type of coal, which is a fossil fuel. It is often referred to as brown coal and is used primarily as a fuel for steam-electric power generation.
• Mica is a group of minerals that can split into thin, tough sheets. It is not a fossil fuel.

Therefore, the correct answer is Lignite because it belongs to the category of fossil fuels. Lignite is formed from the remains of plants that lived millions of years ago, which makes it a source of stored energy that can be burned for heat and power.

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The world's busiest shipping routes are found on the Atlantic Ocean. This ocean plays a crucial role in global trade and transportation due to several factors:

• Location: The Atlantic Ocean is strategically located between the continents of North America, Europe, and Africa. This positioning makes it an important corridor for trade between the densely populated and economically developed regions, including the United States, Canada, Western Europe, and parts of Africa.
• Economic Activity: Countries bordering the Atlantic Ocean, such as the United States, European countries, and Brazil, are some of the world's largest economies. As such, there is a high volume of goods being exchanged across the Atlantic Ocean, contributing to its status as a busy shipping route.
• Major Ports: The Atlantic Ocean hosts several significant ports like Rotterdam, Antwerp, Hamburg, New York, and Shanghai, to name a few. These ports serve as major hubs for commerce, where goods are received, processed, and shipped globally, adding to the traffic on this ocean.
• Historical Significance: Historically, the Atlantic Ocean has been a primary route for exploration and trade since the Age of Discovery. This long-standing use has established robust shipping routes that continue to be essential for international trade.

While other oceans like the Pacific and Indian Oceans are also important for global trade, the Atlantic Ocean remains particularly significant due to its connectivity and the economic powerhouses it links. The Antarctic Circle is not a major route due to its harsh environmental conditions and minimal human inhabitation, which reduces commercial sea traffic in that region.

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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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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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Quartzite, schist, and marble are all examples of metamorphic rocks.

Here's why:

• Metamorphic Rocks: These are rocks that have undergone a transformation due to intense heat and pressure. This process, called metamorphism, alters their original form or mineral composition without melting them.
• Quartzite: This forms from sandstone, a sedimentary rock, that has been exposed to heat and pressure, resulting in a very hard, durable rock.
• Schist: This rock is typically formed from shale, another sedimentary rock, or sometimes from basalt, an igneous rock. It has a shiny appearance due to the presence of mica minerals.
• Marble: This is formed from limestone, a sedimentary rock that undergoes recrystallization under high heat and pressure, resulting in a rock that is often used in sculpture and architecture.

Sedimentary Rocks are formed from the accumulation of sediments, while Igneous Rocks are formed from the cooling and solidification of magma or lava. Volcanic rocks are a subset of igneous rocks that specifically form from lava at the earth's surface. Thus, quartzite, schist, and marble do not fall under these categories.

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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 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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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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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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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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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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In the context of settlement types and their sizes, the largest is a megalopolis.

Let me explain this in simple terms:

• **City:** A city is a large and permanent settlement with a significant population and infrastructure. It is larger than a town but smaller than the other types of settlements listed here.
• Agglomeration: This term generally refers to an area where multiple cities or towns are grouped together, sharing infrastructure and services but still remaining as distinct entities. It is more about the process of these settlements growing together.
• Conurbation: A conurbation is a region that consists of a number of cities or towns which have merged together over time through population growth and expansion. They are physically connected but maintain individual identities.


• Megalopolis: A megalopolis is a massive urban region made up of multiple large cities and their surrounding areas, which have expanded to merge into one continuous urban area. It's much larger than a conurbation. One classic example is the Northeastern megalopolis in the USA, which includes cities like Boston, New York City, Philadelphia, Baltimore, and Washington, D.C.

In summary, of all the settlement types listed, a megalopolis is the largest as it comprises multiple, even significant urban areas that have expanded to form a vast, continuous area.

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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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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 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 development of hydro-electric power in Nigeria is least affected by the availability of suitable sites for dams. While suitable sites are necessary for building dams, other factors such as a regular supply of water and high mountains are more critical for hydro-electric power development.

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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 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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Pie charts are not suitable for representing data with wide extremes, as they are better suited for showing proportions and percentages.

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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 system of cultivation of tropical commercial crops estates is known as plantation agriculture.

Plantation agriculture is a type of farming where a single crop, often a cash crop, is grown on a large area of land. This method is commonly seen in tropical areas where conditions favor the growth of certain commercial crops like tea, coffee, rubber, cocoa, and palm oil.

The defining characteristics of plantation agriculture include:

• Large Scale Production: Crops are grown on expansive estates, which enable significant quantities to be produced.
• Monoculture: Typically, only one type of crop is cultivated for commercial purposes at a time, making it a form of monoculture.
• Capital-Intensive: It often requires heavy investment in machinery, infrastructure, and labor.
• Export-Oriented: The crops grown are usually intended for international trade, contributing to the economy of the region.
• Scientific Techniques: Utilizes advanced agricultural technologies and scientific methods to maximize yield and productivity.

This system significantly contributes to the economies of tropical regions by generating foreign exchange and providing employment opportunities.

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

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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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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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The Ogbunike Cave is a popular tourist destination located **near Onitsha in Anambra State**. This cave is part of a large system of limestone caves and is known for its historical and cultural significance to the people of the region. It's situated in the southeastern part of Nigeria and is associated with numerous legends and stories that reflect its importance to local traditions. Therefore, the correct location for Ogbunike Cave is **near Onitsha in Anambra State**.

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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.