WAEC SSCE - Geography - 2015

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Relief rainfall is common around highland areas. When moist air is forced to rise over a mountain or a highland area, it cools and condenses, leading to the formation of clouds. The clouds then release precipitation in the form of rainfall, known as relief rainfall. The amount of rainfall depends on the height of the mountain, the strength of the prevailing winds, and the amount of moisture in the air. Highland areas are often characterized by heavy rainfall due to relief rainfall. This is because they have a high altitude that forces moist air to rise, leading to the formation of clouds and rainfall. In contrast, lowland areas and deserts typically receive little rainfall because they do not have significant topographic relief to force air to rise and form clouds. Overall, relief rainfall is common around highland areas and plays an important role in shaping the climate and ecosystems of these regions.

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Ash and cinder cones are associated with volcanic eruptions. When a volcanic eruption occurs, magma and ash are expelled from the volcano. Ash and cinder cones are formed when ash and cinders pile up around the volcanic vent, creating a cone-shaped structure. These cones are formed from smaller, more explosive eruptions, and are typically found in areas with a history of volcanic activity.

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Stalactites, swallow holes, and caverns can be found in limestone regions. Limestone is a type of sedimentary rock that is made up of calcium carbonate, and it is often formed in areas where there were once shallow seas or ancient coral reefs. Over time, the limestone can be dissolved by water, which creates caves, caverns, and other unique geological formations like stalactites and swallow holes. These formations are most commonly found in regions where limestone is abundant, such as the karst regions of Europe, Asia, and North America.

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The effect of rural-urban migration on the source region is rural depopulation. This means that people are moving away from rural areas to urban areas, which can result in a decrease in the population of the rural region. This can have various consequences, including a reduction in the workforce available for agriculture and other rural-based industries, as well as a decrease in the demand for goods and services in the area. Additionally, rural depopulation can lead to a decline in infrastructure and services in the region, as there are fewer people to support them. Ultimately, rural depopulation can have a significant impact on the social, economic, and environmental conditions of the source region.

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To calculate the population density of a country, you need to divide the total population of the country by its total area. In this case, the population of the country is 20,000,000 and its size is 1,000,000 km2. So, to calculate the population density, you can divide 20,000,000 by 1,000,000. 20,000,000 / 1,000,000 = 20 Therefore, the population density of this country is 20 persons/km2.

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The fourth planet from the sun in the solar system is Mars. Mars is commonly known as the Red Planet due to its reddish appearance from Earth. It is named after the Roman god of war, likely because of its reddish color, which is reminiscent of blood. Mars is also known for having the largest volcano and the deepest canyon in the solar system. Its atmosphere is composed primarily of carbon dioxide, and it is considered a possible location for future human exploration and colonization.

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Ede is a settlement in Nigeria, and the type of settlement is "linear." A linear settlement is a type of settlement that forms along a road, river, or any other linear feature. In the case of Ede, it is located along a major road that connects it to other nearby towns and cities. The houses and buildings in Ede are typically arranged in a long line along this road, forming a linear pattern of settlement. This type of settlement pattern is common in areas where transportation is important for trade and commerce.

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Igneous rock is formed by the solidification of molten magma or lava. As a result, it is characterized by a crystalline nature, meaning that it is composed of interlocking crystals that have grown as the magma or lava cooled and solidified. These crystals can vary in size depending on the rate at which the magma or lava cooled. Igneous rocks can have a range of textures, from very fine-grained to coarse-grained, depending on the cooling rate. Therefore, the characteristic of igneous rock is that it is crystalline in nature.

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The high rate of population growth in West Africa is best explained by the combination of high birth rate and low death rate. Birth rate refers to the number of births per 1,000 people in a population, while death rate refers to the number of deaths per 1,000 people in a population. In West Africa, the birth rate is high due to a number of factors, including a lack of access to family planning and birth control, cultural and religious beliefs that favor large families, and the role of children in providing labor and support for aging parents. At the same time, improvements in healthcare and sanitation have led to a decrease in the death rate, meaning that more people are surviving into adulthood and having children of their own. As a result, the population of West Africa has been growing rapidly, leading to a range of social, economic, and environmental challenges for the region.

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The major trading partners of the Anglophone West African countries are Britain, USA, Germany and Japan. This means that these countries engage in the most trade with the Anglophone West African countries, which include Gambia, Ghana, Liberia, Nigeria, and Sierra Leone. These trading partners provide these countries with various goods and services and also create job opportunities for their citizens.

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Coastal erosion refers to the gradual wearing away of land and cliffs along a coastline by the action of waves, currents, tides, and wind. The extent of coastal erosion depends on a number of factors, but one of the most significant factors is the nature of the waves. The strength, frequency, direction, and height of waves are all important factors in determining the extent of coastal erosion. For example, powerful waves that crash against the shore with great force can erode the coastline more quickly than gentle waves that lap at the shore. The shape and angle of the shoreline also play a role in determining the extent of coastal erosion. Therefore, the extent of coastal erosion depends on the nature of the waves, including their strength, frequency, direction, and height.

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The remains of eroded highland in desert and semi-desert environments are commonly called inselbergs. Inselbergs are isolated hills or mountains that rise abruptly from flat surroundings due to their more resistant rock composition. They are often remnants of once continuous rock layers that have been eroded away by wind, water, or other natural forces, leaving only the hard and resistant rock formations behind. Inselbergs are typically found in arid regions such as deserts and semi-deserts, where erosion is more pronounced due to the lack of vegetation and the prevalence of strong winds and sporadic rainfall. The term "inselberg" comes from the German word meaning "island mountain", referring to the isolated nature of these formations amidst flat terrain.

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The gradual breakdown of rocks in situ by either physical or chemical process is called weathering. Weathering is a natural process that occurs over time and involves the physical and chemical breakdown of rocks and minerals. Physical weathering involves the breakdown of rocks into smaller pieces by the action of temperature changes, abrasion, or freeze-thaw cycles. Chemical weathering, on the other hand, involves the breakdown of rocks through chemical reactions, such as oxidation or hydrolysis. Both types of weathering can occur together, leading to the gradual breakdown of rocks over time. Weathering is an important process in the formation of soil, as the breakdown of rocks creates the mineral particles that make up soil. It is also an important factor in the shaping of landscapes, as weathering can contribute to the formation of distinctive landforms such as canyons or karst topography.

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The environmental resource that is non-renewable from the options provided is minerals. Minerals are naturally occurring substances that are extracted from the earth for use in a variety of industries such as construction, electronics, and manufacturing. Unlike renewable resources like rain, water, and oxygen, which can be replenished over time, minerals are finite and can only be mined and extracted from the earth's crust. Once a mineral deposit is exhausted, it cannot be replaced or replenished, making it a non-renewable resource. Therefore, it is important to manage and use mineral resources in a sustainable way to ensure their availability for future generations.

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One relative advantage of water transport over road transport is its capacity for carrying bulky goods. Water transport involves the movement of goods on waterways such as rivers, lakes, and oceans. These waterways offer a cheaper means of transportation, particularly for bulky goods that are too heavy for road transportation. Water transport vessels such as ships, barges, and boats have a large carrying capacity that allows them to carry goods in large quantities. This makes it an efficient mode of transport for goods such as crude oil, coal, and other heavy materials. Additionally, water transport is not affected by traffic congestion on the roads, making it a reliable means of transportation for large quantities of goods.

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One of the problems limiting the achievement of the objectives of the Economic Community of West African States (ECOWAS) is the strong colonial ties that exist between member countries and their former colonial powers. The legacy of colonialism has created many challenges for the West African region, including unequal access to resources, limited economic development, and political instability. Many countries in the region continue to rely heavily on their former colonial powers for trade and investment, which can limit their ability to develop independent economic policies and strategies. Furthermore, the colonial powers established arbitrary borders and boundaries that separated ethnic groups, creating social and political tensions that still exist today. This has made it difficult for ECOWAS to promote regional integration and cooperation, as member states often have competing interests and priorities. Overall, the strong colonial ties between member countries and their former colonial powers have created many obstacles to achieving the objectives of ECOWAS, including economic development, political stability, and regional integration.

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Population density is the number of people living in a unit area of land. It is usually expressed as the number of individuals per square kilometer or square mile. It is an important concept in geography and demography because it helps to measure the concentration of people in a particular area and to understand the relationship between people and their environment. The higher the population density in an area, the greater the pressure on the available resources and the environment.

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The temperature decreases as altitude (height above sea level) increases. This is because the air becomes less dense as altitude increases, which causes it to cool down. The rate at which the temperature decreases with altitude is called the lapse rate, which is usually around 6.5 degrees Celsius per 1000 meters. In this case, the mountain is 6000 meters above sea level, so the temperature at the top of the mountain can be estimated as follows: Temperature change = Lapse rate x Altitude change Temperature change = 6.5 degrees Celsius/1000m x 6000m Temperature change = 39 degrees Celsius Since the starting temperature at the foot of the mountain is 20 degrees Celsius, we need to subtract the temperature change from this to get the temperature at the top of the mountain: Temperature at top of mountain = Starting temperature - Temperature change Temperature at top of mountain = 20 degrees Celsius - 39 degrees Celsius Temperature at top of mountain = -19 degrees Celsius Therefore, the temperature at the top of the mountain is -19.0oC.

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The cheapest mode of transport for the conveyance of bulky goods across countries is water transport. This is because water transport is the most fuel-efficient mode of transport and can carry large volumes of goods at once, making it more cost-effective than other modes of transport like air, land, or pipeline. Water transport also has the advantage of being able to access many locations that are not easily accessible by land or air, making it a preferred mode of transport for bulk goods like crude oil, coal, and agricultural products. Additionally, water transport is a reliable and safe mode of transport, which makes it a popular choice for international trade.

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An eclipse of the moon occurs when the Earth comes between the sun and the moon. During a lunar eclipse, the Earth blocks the sun's light from reaching the moon, causing the moon to appear darkened or reddish in color. This occurs because the Earth casts its shadow onto the moon, which is why it is also called a "shadow play". A lunar eclipse can only occur during a full moon phase, when the sun, Earth, and moon are aligned in a straight line. However, it does not occur during every full moon because the moon's orbit is tilted relative to the Earth's orbit around the sun. In contrast, a solar eclipse occurs when the moon passes between the sun and the Earth, blocking the sun's light from reaching parts of the Earth. Overall, the occurrence of a lunar eclipse is a result of the relative positions and movements of the Earth, moon, and sun in space.

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One of the features that could be found in the upper course of rivers is a waterfall. The upper course of a river is the section closest to its source, where the river is typically narrow and has a steep gradient. Waterfalls often form in the upper course of a river when a band of hard rock overlies softer rock that is more easily eroded by the flowing water. The softer rock is gradually eroded away, leaving a steep drop or waterfall over the hard rock layer. Ox-bow lakes, on the other hand, are formed in the lower course of a river when the river meanders or bends and erodes the outer bank, causing the river to cut a new channel and leave a curved lake behind. Deltas are formed at the mouth of a river, where the river meets the sea or a lake and deposits sediment, creating a fan-shaped landform. Levees are raised banks that form along the sides of a river as a result of sediment deposition during flooding events. Overall, waterfalls are a common feature found in the upper course of rivers, while ox-bow lakes, deltas, and levees are typically found in the lower course of rivers.

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The type of rainfall that occurs when two air masses of different temperatures and other physical properties meet is cyclonic rainfall. When a warm air mass and a cold air mass meet, the warm air mass rises above the cold air mass, creating a low-pressure zone. As the warm air rises, it cools and condenses, leading to the formation of clouds and precipitation. This type of rainfall is called cyclonic rainfall because it is associated with the movement of cyclones and other low-pressure systems. Cyclonic rainfall is common in areas where air masses of different temperatures meet, such as along fronts, which are boundaries between air masses.

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The part of the earth's crust which is made up of silica and alumina is called Sial. Sial is the upper layer of the Earth's crust, which is composed primarily of silicon and aluminum. The name "sial" is derived from the first two letters of silicon and aluminum. Sial is less dense than sima, which is the lower layer of the crust that is made up of silica and magnesium. The sial layer is typically thicker beneath continents than beneath oceanic crust, as it forms the underlying structure for the continents.

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The correct option is: "Youth migrate to urban areas in search of jobs." Intercommunity relationship refers to the interaction between different communities or groups living in the same geographical area. In this context, youth migration from rural to urban areas is a common phenomenon and a factor that shapes the relationship between rural and urban communities. As young people move to cities in search of better employment opportunities and quality of life, it can create tension and competition for resources, as well as cultural differences between urban and rural communities.

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Cattle ranching is not common in the forest region of West Africa because of the presence of tsetse flies. Tsetse flies transmit a disease called trypanosomiasis, also known as sleeping sickness, to cattle. This disease can be fatal and can significantly reduce the productivity of the cattle. Tsetse flies are prevalent in forested areas because they rely on forest animals for blood meals. As a result, the presence of tsetse flies in the forest region of West Africa makes it difficult for cattle to thrive, hence the limited occurrence of cattle ranching in the area.

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Wind erosion is common in arid areas because the wind speed is high and there are few wind breaks. Arid areas are characterized by low precipitation and vegetation cover, which exposes the soil to the erosive power of the wind. The wind transports sand and dust particles, which are then deposited in other areas. The lack of vegetation cover reduces the ability of the soil to resist erosion by the wind. Wind breaks, such as trees or other types of vegetation, can reduce the wind speed and help to protect the soil from erosion. However, in arid areas, the lack of vegetation cover means that there are few natural wind breaks to protect the soil. Therefore, wind erosion is a common phenomenon in such areas.

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The core of the earth is also called the barysphere. It is the central part of the Earth, consisting of a solid inner core and a liquid outer core. The inner core is believed to be composed mainly of iron and nickel, while the outer core is also composed of iron, nickel, and other elements. The barysphere is an important part of the Earth's structure, as it is responsible for generating the Earth's magnetic field, which is important for life on Earth.

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The upfolded portion of a fold mountain is called an anticline. A fold mountain is a type of mountain that is formed when rock layers are subjected to pressure and folded. Anticlines are formed when the rock layers are folded upwards, creating an arch-like shape. The highest point of the anticline is called the crest, while the lowest point is called the trough. Anticlines can be found in many different types of rock formations and are often associated with oil and gas deposits, which can be trapped in the folds of the rock.

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The usefulness of import tariff on imported goods is the protection of infant industries. This means that imposing import tariffs on certain goods makes them more expensive for local consumers, which may discourage people from buying them and instead purchase locally produced goods. This will help to support local industries and prevent foreign companies from dominating the market. By protecting infant industries, governments can help them to grow and become more competitive in the long run.

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During equinox, all places across the globe experience equal lengths of day and night. This is because during the equinox, the plane of the Earth's equator passes through the center of the Sun, which causes the Sun to be directly above the equator. As a result, the daylight and darkness hours are approximately equal in duration all over the world, regardless of latitude. This happens twice a year, around March 20th-21st and September 22nd-23rd, and marks the change of seasons from winter to spring, and from summer to autumn, respectively.

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The instrument used for measuring atmospheric pressure is a barometer. A barometer is an instrument that measures atmospheric pressure and is commonly used in weather forecasting. It works by balancing the weight of mercury or aneroid capsules with the weight of the atmosphere. As air pressure changes with the weather, the mercury or capsule moves up or down, indicating changes in pressure. The unit of measurement for atmospheric pressure is usually in millibars or inches of mercury (inHg).

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Whenever a volcanic eruption occurs, gases and molten magma are ejected from the volcano. The gases, such as steam and sulfur dioxide, can be harmful to humans and the environment. The molten magma can flow out of the volcano and form lava flows, which can be very destructive to surrounding areas. Sometimes the eruption can also lead to the formation of volcanic ash and rocks that are ejected into the atmosphere, which can cause significant damage to buildings, crops, and infrastructure. Therefore, volcanic eruptions are potentially hazardous natural events.

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The rock type that involves stratification is sedimentary rock. Stratification refers to the layering of rocks that occurs as sediments are deposited over time. Sedimentary rocks are formed from the accumulation and cementation of sediments, which can include particles of sand, clay, and other materials. As these sediments are deposited in layers, they become compacted and cemented together over time, creating a layered rock structure. This layering, or stratification, is often visible in sedimentary rocks and can provide important information about the geologic history of an area, including the types of sediments that were deposited and the environmental conditions that existed at the time. In contrast, igneous rocks are formed from the cooling and solidification of molten rock, while metamorphic rocks are formed from the alteration of pre-existing rocks through heat and pressure. Volcanic rocks, on the other hand, are a type of igneous rock that is formed from lava or magma that has erupted onto the Earth's surface. These types of rocks do not typically exhibit stratification in the same way that sedimentary rocks do.

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The feature of volcanic origin is a sill. A sill is a type of igneous intrusion formed when magma solidifies between layers of sedimentary rock. It is a horizontal sheet-like body of volcanic rock that forms when magma is forced into an existing crack or between layers of sedimentary rock and then solidifies. Sills can range in thickness from a few centimeters to hundreds of meters and can cover large areas. In contrast, a zeugen is a ridge formed by erosion and weathering of horizontal sedimentary rock layers, while loess is a type of sedimentary deposit consisting of fine-grained materials such as silt and clay that have been deposited by wind. A gorge is a narrow valley with steep, rocky walls formed by erosion from a river or other water source. Overall, the feature of volcanic origin is a sill, which is an important geological structure that can provide clues about the geological history of a region.

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Without knowledge of the specific mapped area, it is difficult to give a definitive answer. However, in many areas, roads are commonly used as a mode of transportation. This is because roads can provide access to remote areas, connect communities, and facilitate the movement of goods and people. Additionally, roads are generally more affordable to build and maintain than other modes of transportation such as rail or air travel. However, in areas with a significant amount of waterways or difficult terrain, river transport or air transport may be more commonly used. In areas with a well-established transportation infrastructure, such as cities or industrialized regions, rail transport may also be commonly used.

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The scale of a map is the relationship between the distance on the map and the actual distance on the ground. It is usually expressed as a ratio or as a statement. In this case, the scale is expressed in statement form. The statement "One centimeter on the map represents half a kilometer on the ground" means that the map has a scale of 1:50,000. This means that one unit of measurement on the map (in this case, one centimeter) represents 50,000 units of the same measurement on the ground (in this case, half a kilometer or 500 meters). In simpler terms, if you measure a distance of one centimeter on the map, it represents a distance of 500 meters (or 0.5 kilometers) on the ground. This scale is commonly used for topographic maps and other detailed maps that show a smaller area.

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The location of market gardening near large cities is best explained by the perishability of products. Market gardening is the small-scale production of fruits, vegetables, and flowers for local consumption. Since the products are highly perishable and have a short shelf life, they need to be transported to consumers quickly to maintain their freshness. By locating the farms near large cities, the distance between the farms and the consumers is reduced, resulting in less time and cost involved in transportation. This ensures that the products reach the market quickly and are sold fresh. Therefore, the correct option from the given choices is "Perishability of products".

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The deposition of fine-grained sand carried over long distances by wind is known as loess. Loess is a type of sediment that consists of fine-grained materials such as silt and clay that have been deposited by wind. These materials are often transported over long distances and can be carried by winds for thousands of kilometers. The particles are typically less than 0.05 mm in diameter and are easily lifted by wind. When the wind carrying the fine-grained sand loses its energy, the sand particles settle and accumulate on the ground, forming deposits of loess. Loess deposits can cover large areas and can be found in many parts of the world, including Europe, China, and the United States. Overall, the deposition of fine-grained sand carried over long distances by wind is known as loess, which is an important type of sediment that can provide insights into the geological history and climate of a region.

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An advantage of solar energy over other sources of energy is that it is easily renewable. This means that the sun provides an almost limitless supply of energy, unlike fossil fuels which are finite and will eventually run out. Solar energy can also be harnessed in many different ways, from large solar farms to small rooftop panels, making it a versatile and widely available source of power. Another advantage is that solar energy does not produce greenhouse gases or other harmful pollutants, making it a cleaner and more environmentally friendly option than many other sources of energy.

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Without knowing the specific mapped area, it's impossible to give a definitive answer. However, in general, animal rearing could be a possible economic activity in the southeastern part of many areas. This is because animal rearing, such as raising cattle or sheep, can be done in areas with grasslands and ample water sources, which are often found in the southeastern regions of many countries. Additionally, animal rearing can provide a source of food and income for local communities, making it a viable economic activity. However, other economic activities such as lumbering, trading, or mining may also be practiced in certain southeastern areas depending on the natural resources and infrastructure available in the region.

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(a) Five factors to consider in the location of an industry

• Raw materials: nearness to the source, especially for bulky, heavy or perishable materials, to cut transport costs.
• Power/energy supply: availability of reliable electricity, gas or fuel to run machines.
• Market: nearness to the consumers of the product, especially for bulky, fragile or perishable finished goods.
• Labour: availability of enough skilled and unskilled workers at reasonable cost.
• Transport: good roads, railways, ports or waterways to move raw materials in and goods out.
• (Also: water supply, capital, land, and government policy.)

(b) Five benefits of industrialisation to a country

• Employment: industries create many jobs and reduce unemployment.
• Economic growth and income: they raise national income (GDP) and government revenue through taxes.
• Foreign exchange: export of manufactured goods earns foreign currency and reduces dependence on imports.
• Development of infrastructure: industrialisation brings roads, power, water and communications and stimulates towns.
• Diversification and self-reliance: it processes local raw materials, adds value, and reduces overdependence on primary products; it also promotes skills and technology.

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(a) Definition of climate

Climate is the average weather conditions of a place recorded and generalised over a long period of time, usually not less than 35 years. It considers elements such as temperature, rainfall, pressure, humidity and wind.

(b) The three climatic belts of the Greek system

The ancient Greeks divided the earth into three temperature zones based on distance from the equator and the angle of the sun's rays:

• The Torrid (Tropical) Zone: Lying between the Tropic of Cancer (\(23\tfrac{1}{2}^\circ\)N) and the Tropic of Capricorn (\(23\tfrac{1}{2}^\circ\)S). The sun is overhead at some time of the year, so it is permanently hot.
• The Temperate Zones: Two belts lying between the tropics and the Arctic Circle (\(66\tfrac{1}{2}^\circ\)N) and Antarctic Circle (\(66\tfrac{1}{2}^\circ\)S). They receive slanting rays and experience moderate, seasonal temperatures.
• The Frigid (Polar) Zones: Two belts lying between the polar circles and the poles. The sun's rays are very oblique, so they are permanently cold.

(c) Three reasons why Koppen's system is the most widely accepted

• It is based on measurable, quantitative data (definite values of temperature and rainfall), so it is precise and can be applied objectively anywhere.
• It links climate closely with natural vegetation, making the classification meaningful and easy to relate to the real world.
• It uses a simple system of letter symbols (A, B, C, D, E, etc.) that is concise, easy to remember and allows detailed sub-division of climatic types.

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(a) Definitions

• (i) Death rate: the number of deaths per 1,000 people in a population in one year. It is also called the crude death rate or mortality rate.
• (ii) Population explosion: a very rapid and sudden increase in the population of an area over a short period, caused mainly by a high birth rate combined with a sharply falling death rate.

(b) Factors that influence death rate in Tropical Africa

• Medical/health facilities: where hospitals, drugs, immunisation and trained personnel are adequate the death rate falls; where they are scarce it rises.
• Food supply and nutrition: adequate, balanced food lowers deaths, while famine and malnutrition raise them.
• Disease: the prevalence of malaria, cholera, HIV/AIDS and other tropical diseases raises mortality.
• Sanitation and clean water: good sanitation and safe water reduce deaths, poor sanitation increases them.
• War, natural disasters and civil unrest, and the general standard of living/poverty, also affect death rates.

(c) Three effects of a growing population in Tropical Africa

• Pressure on land and food: more mouths to feed lead to food shortage, land fragmentation and over-cultivation.
• Strain on social services and infrastructure: schools, hospitals, housing, water and roads become overstretched.
• Unemployment and overcrowding: too many job-seekers cause high unemployment, rural-urban migration, slums and environmental degradation.

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(a) Explanation of terms

1. Rotation of the earth: This is the spinning of the earth on its own axis from west to east. The axis is an imaginary line drawn through the North and South Poles, inclined at \(66\tfrac{1}{2}^\circ\) to the plane of the earth's orbit (or \(23\tfrac{1}{2}^\circ\) from the vertical). One complete rotation takes about 24 hours and gives rise to day and night.
2. Revolution of the earth: This is the movement of the earth in its orbit around the sun. The earth completes one revolution in about \(365\tfrac{1}{4}\) days (one year), moving in an elliptical path while its axis remains tilted and pointing in the same direction (parallelism of the axis).
3. Equinox: This is the time, occurring twice a year (around 21 March and 23 September), when the sun is overhead at the equator and day and night are of equal length (12 hours each) all over the world. The word means "equal night".

(b) Three effects of the revolution of the earth

• It causes the seasons of the year (spring, summer, autumn and winter) because of the changing position of the earth relative to the sun combined with the tilt of the axis.
• It causes varying lengths of day and night at different times of the year, especially away from the equator.
• It causes the apparent migration of the overhead sun between the Tropic of Cancer and the Tropic of Capricorn, and forms the basis of the calendar year of about \(365\tfrac{1}{4}\) days, which necessitates a leap year.

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(a) Problems of agricultural development in Nigeria

• Poor/traditional methods: reliance on crude tools (hoe and cutlass) and low technology gives low yields.
• Land tenure system: fragmented, communally owned holdings make large-scale mechanised farming difficult.
• Inadequate finance/credit: farmers lack capital and loans to buy inputs and machinery.
• Pests and diseases attack crops and livestock and reduce output.
• Poor storage and processing facilities, leading to heavy post-harvest losses.
• Unreliable rainfall and drought in the north, and flooding elsewhere.
• Poor transport and marketing, and low, fluctuating prices that discourage farmers.
• Rural-urban migration draining the young farm labour force, and shortage of extension services and improved inputs.

(b) Solutions to the problems

• Mechanise farming and supply improved seeds, fertilisers and modern tools to raise yields.
• Reform the land tenure system to allow access to larger farm holdings.
• Provide credit and finance through agricultural banks and government loan schemes.
• Control pests and diseases with chemicals, vaccination and research.
• Build storage, processing and preservation facilities to cut losses.
• Expand irrigation to overcome unreliable rainfall.
• Improve rural roads, transport and marketing, and guarantee fair prices.
• Strengthen extension services and training, and make farming attractive to check migration.

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(a) Sketch map of Nigeria showing vegetation areas

Key locations shown:

1. Mangrove swamp vegetation: Niger Delta, around Port Harcourt.
2. Rain forest vegetation: south-western Nigeria, around Benin City.
3. Guinea savanna vegetation: the Middle Belt, around Lokoja.
4. Sudan savanna vegetation: northern Nigeria, around Kano.

(b) Three trees found in the forest zone of Nigeria

1. Mahogany
2. Iroko
3. Obeche

(c) Contributions of forest vegetation to the economic development of Nigeria

1. Supply of industrial raw materials: Forests provide timber, pulp, latex, resins and other materials used in sawmills, furniture making, paper production and allied industries.
2. Employment opportunities: Forestry creates jobs for lumbermen, forest guards, carpenters, furniture makers, timber merchants, hunters and transporters.
3. Foreign-exchange earnings: Timber and forest products such as logs, plywood, veneer and rubber can be exported, thereby earning revenue and foreign exchange for Nigeria.
4. Provision of building materials and fuel: Forests supply poles, planks, roofing materials and firewood used in housing construction and domestic energy.

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(a) Meaning of environmental hazards

Environmental hazards are natural or human-induced events, processes or conditions in the environment that pose a threat to human life, property, economic activities and the natural landscape. They are potentially damaging occurrences within the biophysical environment that can result in loss of life, injury, destruction of property or disruption of social and economic life.

(b) Three examples of environmental hazards

1. Flooding.
2. Drought and desertification.
3. Earthquakes (or volcanic eruptions, landslides, soil erosion, deforestation and pollution).

(c) Five ways of preventing desert encroachment

1. Afforestation and reforestation: Planting trees and grasses over bare land binds the soil with roots, reduces wind speed at ground level and returns moisture to the atmosphere, so the desert margin is held back.
2. Establishment of shelter belts (windbreaks): Rows of drought-resistant trees planted at right angles to the prevailing wind reduce wind erosion and prevent sand from being blown onto farmland and settlements.
3. Control of overgrazing: Limiting the number of animals per unit of land and practising rotational grazing allows vegetation to recover, keeping the ground covered so that wind and sun cannot strip and dry the soil.
4. Control of bush burning and deforestation: Enforcing laws against indiscriminate burning and tree felling preserves the protective vegetation cover that shields the soil from drying and erosion.
5. Provision of irrigation and water conservation: Building dams, boreholes and irrigation channels supplies water to dry areas, enabling continuous cultivation and vegetation growth that hold the land against advancing sand.

Public enlightenment on land conservation and the use of alternative fuels (to reduce dependence on firewood) also help to check desert encroachment.

Détails de la réponse

(a) Four commodities exported from my country (Nigeria) to a European country (for example the United Kingdom)

• Crude petroleum (oil)
• Cocoa
• Rubber
• Tin and other solid minerals (also timber, hides and skins)

(b) Four reasons for the low volume of trade among West African countries

• Similar products: the countries produce and export the same primary goods (cocoa, groundnuts, palm produce, minerals), so they need one another's goods little and compete rather than trade.
• Poor transport links between the countries, with few good roads and rail lines connecting them, raising the cost of movement.
• Different currencies and colonial trade ties that bind each country more to Europe than to its neighbours.
• Trade barriers such as high tariffs, customs delays, language differences and border restrictions, plus smuggling and lack of industrial goods to exchange.

(c) Four ways of improving trade among West African countries

• Strengthen ECOWAS and remove tariffs and other trade barriers to form a free-trade area.
• Improve transport and communication - build international roads, railways and telecommunication links between the countries.
• Diversify economies and industrialise so that countries produce a wider range of goods to exchange.
• Adopt a common currency and harmonise trade policies, and set up joint industrial and marketing projects.

Détails de la réponse

(a) Outline map of Nigeria showing the air masses and the ITCZ in July

In July, moist Tropical Maritime (T.M.) south-westerly winds cover virtually the whole of Nigeria. The ITCZ lies north of Nigeria, approximately along latitude 20°N, and the dry Tropical Continental (T.C.) north-easterly winds are restricted to the area north of the ITCZ. Lagos, Ibadan and Enugu are shown within the area occupied by the T.M. air mass.

(b) Characteristics of the wet season in Nigeria

1. The prevailing air mass is the moist Tropical Maritime air mass, which blows as south-westerly winds from the Atlantic Ocean.
2. Rainfall is heavy and frequent, often accompanied by thunderstorms and squall lines.
3. Relative humidity is high, generally about 80% to 100%, and cloud cover is extensive.
4. Rainfall is greatest and lasts longest in the south, decreasing northwards. The south has a double rainfall maximum, with an August break, while the north has a single maximum.

(c) Two cash crops grown during the wet season in Nigeria

1. Cocoa
2. Oil palm

Détails de la réponse

(a) Three types of mountains

• Fold mountains (e.g. the Alps, Himalayas, Atlas).
• Block (fault) mountains or horsts (e.g. the Ruwenzori).
• Volcanic mountains (e.g. Mount Cameroon, Kilimanjaro).

(Others include residual mountains formed by denudation, e.g. inselbergs.)

(b) Four ways mountains are important to man

• Source of rivers: High mountains induce heavy rainfall and act as water catchment areas, feeding rivers used for water supply, irrigation and hydro-electric power.
• Climatic barrier and rainfall: They force moist air to rise and cool, giving relief (orographic) rainfall on the windward side that supports farming.
• Mineral and forest resources: Mountains contain valuable minerals and timber, and their slopes support forestry and grazing.
• Tourism, defence and settlement: Their scenery attracts tourists, they served historically as natural defensive barriers, and cool highland climates favour settlement and plantation crops such as tea and coffee.

(c) Two problems caused by mountains

• They hinder transport and communication, making the construction of roads and railways difficult and expensive.
• They create a rain-shadow effect, leaving leeward areas dry, and their steep slopes encourage soil erosion and landslides while limiting the amount of land available for farming and settlement.