WAEC SSCE - Geography - 2000

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One major problem in agricultural development in Nigeria is the insufficient storage facilities. Agricultural production in Nigeria is often hampered by inadequate storage facilities, leading to significant post-harvest losses. Farmers are often unable to sell their produce at the right time and prices due to inadequate storage facilities, leading to a loss of income. Additionally, insufficient storage facilities can also lead to food insecurity and inflation. Hence, improving the storage facilities in Nigeria is crucial to boost agricultural development and improve food security.

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The best solution to the rapid depletion of forest resources in West Africa is to introduce forest conservation techniques. These techniques include sustainable forestry practices that allow for the harvesting of timber and other forest products without damaging the forest ecosystem. This can be achieved by implementing selective logging, which targets only mature trees and leaves the younger trees to continue growing. Other techniques include reforestation, which involves planting new trees in areas that have been deforested, and agroforestry, which combines tree planting with agricultural practices to create sustainable farming systems. Reserving hectares of land for plantations may not be sustainable in the long run and could lead to the displacement of local communities. Importing wood from other countries would also not address the root cause of deforestation in West Africa and could be more expensive than implementing conservation techniques. Employing more forest guards could help to enforce existing regulations, but it would not address the underlying causes of deforestation. Therefore, introducing forest conservation techniques is the best solution to ensure the long-term sustainability of West Africa's forest resources.

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Détails de la réponse

The difference in longitude between London (0°) and Sydney (approximately 150°E) is 150 degrees. Since the Earth rotates 360 degrees in 24 hours, each degree of longitude corresponds to 4 minutes of time difference between two places. Therefore, to calculate the time difference between London and Sydney, we need to multiply the difference in longitude by 4. 150 degrees x 4 minutes/degree = 600 minutes or 10 hours So, Sydney is 10 hours ahead of London. If it is 12:00 pm (noon) in London, it would be 10:00 pm in Sydney on the same day. Conversely, if it is 12:00 pm (noon) in Sydney, it would be 2:00 am in London on the same day.

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Granite rocks contain silica, aluminum, and iron. This is because granite is an igneous rock that is primarily made up of quartz, feldspar, and mica minerals. Quartz is composed of silicon and oxygen, while feldspar contains silicon, oxygen, aluminum, and other elements such as sodium, calcium, or potassium. Mica is a group of minerals that includes silicon, oxygen, aluminum, and other elements such as iron, magnesium, or potassium. Therefore, the combination of these minerals in granite rocks results in a high content of silica, aluminum, and iron.

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The Shiroro Gorge can be found on River Kaduna. The Kaduna River is a major tributary of the Niger River and is located in the northern part of Nigeria. The Shiroro Gorge is situated on the Kaduna River in Niger State, Nigeria, and is known for its hydroelectric power generation plant, the Shiroro Hydroelectric Power Station.

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Détails de la réponse

The Earth rotates on its axis from west to east. This means that when we look at a map, the Sun appears to rise in the east and set in the west. The rotation of the Earth is what causes day and night. As the Earth rotates, different parts of the planet are exposed to the Sun's rays, creating the cycle of day and night. It takes the Earth approximately 24 hours to make one complete rotation on its axis. This rotation also causes the Coriolis effect, which affects global weather patterns and ocean currents.

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Détails de la réponse

The middle course of a river normally shows meanders. Meanders are bends or loops in a river's channel that are characterized by the erosion of the outer banks and deposition of sediment on the inner banks. The middle course of a river is where the gradient of the river is less steep and the water flow is slower, so the river has less energy to transport sediment. As a result, the river meanders and forms curves and loops in its course.

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The bulk of Nigeria timber is obtained from the rain-forest. The rain-forest is a type of forest characterized by high rainfall and biodiversity, and is found in the southern part of Nigeria. The rain-forest in Nigeria is a major source of timber and other forest products, such as rubber, palm oil, and cocoa. The rain-forest also provides habitats for a diverse range of flora and fauna, and plays an important role in regulating the global climate.

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The climatic type found on the western margins of continents between altitude 300 and 400 North and South of the Equator is the Mediterranean climate. This climate is characterized by hot, dry summers and mild, rainy winters. It is typically found along the western coastlines of continents where there is a cold ocean current offshore and a high-pressure system over the nearby landmass. The combination of these factors results in a mild, rainy winter season and a warm, dry summer season. The vegetation in this region is typically dominated by evergreen shrubs and trees, such as the Mediterranean oak and olive tree.

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Altitude is not an element of climate, as it is a characteristic of the physical geography of an area rather than a component of climate. Climate is generally defined as the long-term average of weather patterns in a particular region, and is influenced by various factors such as temperature, air pressure, and precipitation, among others. Altitude, on the other hand, refers to the height of land above sea level, and can affect climate indirectly by influencing factors such as temperature and precipitation, but it is not a direct element of climate itself. However, altitude can be used as a means of classifying different climate types, such as highland climates, which are found at high elevations and are characterized by cooler temperatures and increased precipitation.

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Desert encroachment can best be controlled by afforestation. Afforestation is the process of planting trees in areas where there were no trees before. Trees help to anchor soil in place and prevent soil erosion caused by wind and water. Additionally, trees absorb carbon dioxide from the atmosphere, which can help to mitigate the effects of climate change. Erecting barriers can help to slow down the movement of sand dunes, but it is not a long-term solution as barriers can eventually become buried by sand. Slopewise cultivation is not effective in areas where there is little rainfall and water is scarce, which is often the case in desert areas. Over-grazing, which is the practice of allowing too many animals to graze on a particular piece of land, can lead to soil degradation and can actually contribute to desertification.

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The major problem facing the utilization of human resources in West Africa is unemployment. Unemployment refers to the situation where people who are willing and able to work cannot find jobs. In West Africa, the problem of unemployment is widespread, particularly among the youth. This can be attributed to a number of factors, including inadequate economic growth, poor education and training systems, and limited job opportunities. Unemployment has significant negative impacts on individuals and the economy at large, including increased poverty and social unrest, reduced productivity, and a loss of human capital. It is important for governments and other stakeholders to address this issue by implementing policies and programs that promote economic growth, improve education and training, and create job opportunities for young people in particular.

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Cement factory is usually located near the source of raw materials. This is because cement is made from raw materials such as limestone, shale, and clay, which are found in abundance in certain geological formations. Transporting these raw materials to distant locations can be expensive and increase the cost of production, hence it is more cost-effective to locate the cement factory near the source of these materials. Additionally, proximity to the raw materials ensures a steady supply for the production process, which can be critical to the success of the factory.

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The planet with rights of circular light and dark bands is Jupiter. This is due to the planet's atmospheric composition and its high winds which create these visible bands. Jupiter is a gas giant planet and its atmosphere is primarily composed of hydrogen and helium, with small amounts of other gases such as methane and ammonia. The planet's strong winds are responsible for creating these distinctive bands, with the lighter bands indicating regions of higher altitude where the gas is cooler, and the darker bands indicating regions of lower altitude where the gas is warmer.

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The most common type of vegetation in northern Nigeria is tropical grassland, also known as savanna. This type of vegetation is characterized by grasses and scattered trees that can withstand long periods of drought and hot temperatures. The savanna is adapted to the region's climate, which is characterized by a long dry season and a short rainy season. The grasses are able to survive and grow during the rainy season, and then become dormant during the dry season. The scattered trees provide shade and help to break the wind. The savanna vegetation is also important for the region's economy, as it supports pastoralism and agriculture, and is a source of timber, firewood, and other products for local communities.

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The world's busiest shipping routes are on the Pacific Ocean and the Atlantic Ocean. This is because the Pacific and the Atlantic oceans are the largest and most heavily trafficked bodies of water on the planet, connecting many of the world's major trading nations. The Pacific Ocean is home to several busy shipping routes, including the Transpacific shipping route, which connects Asia and North America. This route is one of the busiest in the world, as it connects many of the world's largest economies, including China, Japan, and the United States. Similarly, the Atlantic Ocean is also a major hub for global shipping. The North Atlantic shipping route connects North America and Europe, while the South Atlantic shipping route links South America, Africa, and Europe. The Atlantic Ocean also serves as a major shipping route for oil and natural gas, with many tankers transporting these resources from the Middle East to Europe and North America. Overall, the Pacific and Atlantic Oceans are key transportation corridors for international trade, and the busiest shipping routes in the world are located in these two oceans.

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Détails de la réponse

Roads constructed to span long distance and across continents are called trans-continental highways. A highway is a public road, usually designed for long-distance travel and usually connecting major cities. A trans-continental highway, therefore, is a highway that spans across entire continents, connecting regions and countries together. These roads are often built to facilitate trade, commerce, and transportation of goods and people. For example, the Pan-American Highway is a trans-continental highway that runs through North, Central, and South America, connecting over a dozen countries. Another example is the Trans-Siberian Highway, which spans across Russia, connecting Moscow to the far eastern regions of the country. These highways play a vital role in promoting economic development, cultural exchange, and regional integration. They also provide important links between countries and regions, enabling the movement of goods and people over long distances.

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The presence of the Namib Desert in South West Africa can be explained by the fact that the coast is washed by the cool Benguela current. This current flows along the southwestern coast of Africa and creates a cold and dry climate. The cool air from the ocean cannot hold much moisture, so it does not rain very often. As a result, the Namib Desert has formed along the coast of South West Africa. The other options are not correct. The area is not too far from the sea because the Namib Desert is located along the coast. The westerlies, which are strong winds that blow from west to east, do not have a significant impact on the formation of the Namib Desert. The distance from the Kalahari Desert, which is located to the east of the Namib Desert, is not a major factor in the formation of the Namib Desert.

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The sea routes mentioned in the options are London-Moscow-Baghdad, London-Cape Town-Melbourne, New York-London-Rotterdam, and Sydney-Suez-London. The question is asking for the option that is not a sea route. Therefore, the correct answer is the option that does not include any sea routes. The first option, London-Moscow-Baghdad, does not include any sea routes. The other options all include travel by sea, either across the Atlantic, Indian or Mediterranean Oceans. Therefore, the answer is: London-Moscow-Baghdad.

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The major characteristic feature that distinguishes heavy industry from light industry is the complexity of the processing technique used in production. Heavy industry involves the production of large, complex, and capital-intensive machinery, equipment, and infrastructure, such as construction materials, mining equipment, and heavy machinery for manufacturing. Heavy industry products require extensive processing and use of advanced and sophisticated manufacturing techniques, which typically involve the use of large-scale machinery and advanced technology. On the other hand, light industry involves the production of smaller, less complex, and less capital-intensive consumer goods such as textiles, clothing, and household appliances. Light industry products typically require less processing and use simpler manufacturing techniques, which usually involve manual labor or semi-automated machinery. Light industry products are generally less costly to produce and require less capital investment than heavy industry products. It's worth noting that the classification of an industry as heavy or light also depends on other factors such as the level of industrial waste, location, and ownership. However, the key distinguishing factor between the two is the complexity of the production process.

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The lower course of a river is usually associated with the formation of ox-bow lakes. This is because the lower course of a river is where the river channel starts to flatten out and widen as it approaches its mouth, usually in a delta or estuary. The river's energy decreases in the lower course, resulting in a slower flow of water and deposition of sediment. Over time, the river erodes its banks and meanders or curves back and forth, creating loops known as meanders. As the meander loop becomes more pronounced, the river may cut through the narrow neck of land at the base of the loop, causing the river to flow along a straighter path, leaving behind an abandoned meander bend or oxbow lake. Therefore, oxbow lakes are formed as a result of the meandering and erosion processes in the lower course of a river.

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Residual mountains are formed when the general level of land is lowered by agents of denudation, such as erosion and weathering, but some areas remain elevated due to the presence of hard and resistant rock. Over time, these areas are shaped by erosion into mountains, which are called residual mountains. The erosion and weathering gradually wear down the softer rocks around them, leaving the harder rocks standing tall. This process can be observed in places like the Appalachian Mountains in the eastern United States, which were once much taller but have been worn down over millions of years by erosion to their current height.

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Import tariffs are imposed on goods entering a country in order to protect the growth of local industries. When a country imposes a tariff on an imported good, it increases the price of that good, making it more expensive than the locally produced alternative. This makes it more attractive for consumers to buy the locally produced product, thereby promoting the growth of local industries. Additionally, the revenue generated from tariffs can be used to subsidize local industries, making them more competitive in the global market. Therefore, import tariffs serve as a protectionist measure for local industries against foreign competition.

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The major problem facing railway transport compared to road transport is the lack of flexibility. Unlike road transport, which can reach almost any destination with a road network, railways are limited by their fixed routes and are not easily adaptable to changes in demand or supply. This means that railway transport cannot easily reach remote or rural areas, and its services may not be available to all customers who require them. In contrast, road transport can be more flexible in terms of routing, scheduling, and pricing, which makes it more accessible and convenient for many people. While other factors such as inadequate manpower, low patronage, and excessive speed can also affect railway transport, the lack of flexibility is the primary issue that limits its effectiveness compared to road transport.

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Détails de la réponse

The tourist center of Ogbunike cave is located near Onitsha in Anambra state, Nigeria. Ogbunike cave is a popular tourist destination in Anambra state and is located about 11 kilometers south of Onitsha, a major commercial city in the state. The cave is located in Ogbunike, a small town in Oyi local government area of Anambra state.

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The outermost layer of the earth is called the "crust." It is the solid, rocky layer that forms the Earth's surface and varies in thickness from around 5-70 kilometers. The crust is composed of different types of rocks and minerals, and it is broken up into tectonic plates that move and interact with each other, causing earthquakes and volcanic activity. The crust is also the layer where all living things exist and where most of our natural resources are found, such as oil, gas, and minerals.

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In the desert region, the most prominent agent of erosion is wind. Due to the scarcity of water in deserts, rainfall and rivers are very limited, and therefore their impact on erosion is minimal. Thunderstorms may cause flash floods and some erosion, but they are relatively rare in deserts. On the other hand, wind erosion is very common in deserts, where strong winds blow constantly and move large amounts of sand and dust. The wind can create various landforms, such as sand dunes, ventifacts, and desert pavements, through the process of abrasion, where particles of sand and dust carried by the wind collide with the exposed rock surfaces and wear them down over time. Therefore, wind is the most significant agent of erosion in the desert region.

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The country that is located in North Africa is Algeria. North Africa is a region that includes countries located in the northern part of the African continent, along the Mediterranean Sea. Algeria is one of the countries located in this region, along with other countries like Morocco, Tunisia, Libya, and Egypt. Zaire (now known as the Democratic Republic of Congo) is a country located in Central Africa, not North Africa. Rwanda is a country located in East Africa, not North Africa. Namibia is a country located in Southern Africa, not North Africa.

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(a) Four factors that led to the high population density in Japan

1. Extensive coastal lowlands and plains: Although Japan is largely mountainous, the limited flat land such as the Kanto, Nobi and Kinki plains concentrates settlement, industry and farming, forcing very high densities onto the small habitable portion.
2. Highly developed industry and commerce: Japan is one of the world leading industrial nations (vehicles, electronics, iron and steel, shipbuilding). The abundance of factory and service jobs in cities like Tokyo, Osaka and Yokohama attracts and holds a large population.
3. Intensive and productive agriculture: The fertile alluvial soils, favourable monsoon rainfall and intensive rice cultivation (double cropping, terracing) support a dense rural population on very little land.
4. Excellent transport and long history of settlement: A dense network of railways, expressways and ports links the crowded core regions, while long-established urban centres have grown continuously over centuries, adding to concentration.

Other acceptable points: good fishing grounds offshore, high standard of living and medical care giving long life expectancy, and government concentration of development in the coastal belt.

(b) Three problems of the high population density in Japan

1. Housing shortage and overcrowding in the large cities, leading to very small dwellings, high rents and pressure on land.
2. Heavy pressure on land for farming, industry and building, causing high land prices and reclamation of the sea.
3. Traffic congestion and environmental pollution (air and water) arising from dense industry and heavy commuter movement in the urban regions.

Also acceptable: strain on social services and disposal of waste.

(c) How these problems are being solved

• Building of high-rise blocks of flats and reclaiming land from the sea to create more space for housing and industry.
• Construction of efficient mass-transit systems such as the bullet train (Shinkansen) and city subways to ease congestion.
• Decentralisation of industry and population to smaller towns and new towns to reduce pressure on the core cities.
• Strict pollution-control laws and the encouragement of family planning to check further rapid growth.

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(a) Combined rainfall and temperature graph for Station X

The monthly figures for the station are set out below. Temperature is plotted on the left-hand vertical axis as points joined by a smooth curve; rainfall is plotted on the right-hand vertical axis as vertical bars, one for each month.

The completed climate graph is shown below.

(b) Calculations

(i) Annual temperature range = temperature of the hottest month minus temperature of the coldest month:

(ii) Mean annual temperature = sum of the twelve monthly temperatures divided by 12:

(c) Climatic type

The station has a small annual temperature range (9\(^{\circ}\)C) with warmth throughout the year, and its highest temperatures (Dec-Feb) fall in the driest months while the heaviest rain (Jun-Aug) comes in the cooler months. Hot, dry summers combined with mild, wet winters identify the station as a Mediterranean (warm temperate western margin) climate. Because the hot dry season occurs in December-February, the station lies in the Southern Hemisphere.

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(a) Location on the outline map of Nigeria

• Gold: Ilesha/Maru-Anka area (Osun and Zamfara/Niger belt of the Basement Complex) – town: Ilesha (or Maru).
• Petroleum: the Niger Delta (Rivers, Bayelsa, Delta States) – town: Port Harcourt (or Warri).
• Columbite: the Jos Plateau – town: Jos (or Bukuru).

(b) Three contributions of mineral resources to the economy of Nigeria

1. Source of government revenue and foreign exchange: crude oil exports supply the greater part of federal revenue and foreign earnings used to finance development.
2. Provision of employment and income: mining, drilling, refining and servicing industries create jobs for many Nigerians, raising incomes and living standards.
3. Basis for industrialisation and infrastructure: minerals supply raw materials and energy (petroleum, natural gas, tin, columbite, limestone) for industries, and mineral revenue funds roads, ports, schools and power projects.

(c) Four factors that limit the exploitation of minerals in Nigeria

1. Shortage of capital for the heavy investment needed in exploration, drilling and machinery.
2. Inadequate skilled manpower and technology, forcing reliance on expensive foreign experts and equipment.
3. Poor transport and infrastructure to many mineral sites, raising the cost of moving ores to processing points and ports.
4. Insecurity, pipeline vandalism and environmental problems (oil spillage, community unrest), plus fluctuating world prices, which discourage steady production.

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(a) A typical soil profile

A soil profile is a vertical section through the soil, from the surface downwards to the underlying parent rock. It reveals a series of distinct layers, called horizons, which differ in colour, texture, humus content and mineral composition. A well-labelled diagram of a typical soil profile is shown below.

Working downwards, the horizons are:

• O horizon (litter layer): the thin surface layer of fresh and partly decayed plant and animal remains (leaf litter and humus).
• A horizon (topsoil / zone of eluviation): a dark, humus-rich mineral layer where biological activity is greatest. Most plant roots and soil organisms occur here, and soluble minerals are washed downward (leached) out of this zone.
• B horizon (subsoil / zone of illuviation): lighter in colour because it contains less humus. Clay and minerals leached from the A horizon (chiefly iron, aluminium and calcium compounds) accumulate here, making it denser and more compact.
• C horizon (regolith): partly weathered, broken fragments of the parent rock from which the true soil above has developed; it acts as a reservoir of fresh minerals.
• R horizon (bedrock): the solid, unweathered parent rock at the base of the profile.

(b) Importance of soil

1. It is the main medium of plant growth, supplying nutrients, water and anchorage for roots.
2. It forms the basis of agriculture and grazing, and therefore of food production; soil type largely determines the kind of farming practised.
3. It is a habitat for micro-organisms, earthworms, reptiles and other soil organisms that recycle nutrients.
4. It provides raw materials for industry, such as sand, clay and limestone.
5. It stores, filters and releases water, and holds the essential minerals needed by plants.
6. It serves as a firm foundation for buildings, roads and other structures.

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(a) Combined rainfall and temperature graph for Station X

The two elements are drawn on the same base line of months but on two different vertical scales: rainfall is shown as columns read against the left-hand scale (in millimetres) and temperature is shown as a smooth line read against the right-hand scale (in degrees Celsius). The paired figures used are:

(b) Calculations

(i) Annual temperature range

The annual temperature range is the difference between the highest and the lowest mean monthly temperatures.

Highest temperature = 21ºC (January and February)
Lowest temperature = 12ºC (June and July)

(ii) Mean annual temperature

Add the twelve monthly temperatures and divide by 12.

(c) Climatic type

The station shows the following features:

• Warm, moderate temperatures throughout the year (range only 9ºC, mean about 16.8ºC), so there is no true cold season.
• Highest temperatures occur in December, January and February (about 20–21ºC) and the lowest in June and July (12ºC). Since summer falls in December–February, the station lies in the Southern Hemisphere.
• The rain comes mainly in the low-sun (winter) season, June–August, reaching a maximum of 112 mm in July, while the high-sun (summer) months of January–February are the driest (17–18 mm). Total annual rainfall is 592 mm.

Warm dry summers combined with mild wet winters and a small temperature range identify the station as a Mediterranean climate (also called the Warm Temperate Western Margin climate), such as that experienced around Cape Town, Perth or central Chile.

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Comparison of the North Central Highlands with the Cross River Plain

(a) Relief and Drainage

(b) People and Settlement

(c) Economic Activities

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(a) Three differences between rail and water transport

Also acceptable: rail follows a fixed inland route and can reach interior areas, while water transport is limited to navigable waterways and coasts.

(b) Four ways transportation can influence economic development (using Nigeria as the named West African country)

1. Opening up of remote areas: roads, rail and waterways make interior farming and mining regions accessible, encouraging production.
2. Movement of raw materials and finished goods: good transport links farms, factories and markets, promoting trade and industry.
3. Encouragement of agriculture and marketing: farmers can move perishable produce quickly to urban markets, raising farm incomes.
4. Employment and growth of towns: transport construction and services create jobs, and towns grow at route junctions and ports (for example Lagos, Kano, Port Harcourt).

Also valid: it promotes tourism, national integration and even distribution of development.

(c) Three problems of rail transport development in developing countries

• Shortage of capital to build and maintain the expensive rail lines and rolling stock.
• Difficult physical relief such as rivers, swamps, mountains and hard rock that raise construction costs.
• Obsolete equipment and poor maintenance leading to frequent breakdowns, derailments and unreliable services, worsened by shortage of spare parts and skilled personnel.

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(a) Outline map of West Africa showing three ECOWAS members and their capital cities

The sketch map below shows the outline of West Africa with three member countries of the ECOWAS shaded and named, and the capital city of each country marked with a dot and named.

The three member countries and their capital cities shown are:

(b) Three objectives of the ECOWAS

1. Promotion of trade and economic integration: to increase and liberalise trade between member states by removing tariffs and other trade barriers so as to build a common market in the sub-region.
2. Free movement of persons, goods, services and capital: to allow citizens, goods and services to move freely across member borders, including the right of residence and establishment.
3. Co-operation and joint development: to promote co-operation and development in economic, social and cultural activities, including the joint development of transport, communication and other infrastructure, and eventually the establishment of a common currency.

(c) Three factors that have limited the full attainment of these objectives

1. Language barrier and strong colonial ties: members are split into English-, French- and Portuguese-speaking blocs with differing colonial links, which hinder easy communication and full co-operation. Some Francophone states also maintain rival sub-regional bodies that work against ECOWAS.
2. Similarity of economic activities and currency problems: most members produce and export the same primary products, so they compete with rather than complement one another, keeping intra-regional trade low. The use of many different national currencies further complicates trade and payments.
3. Political instability and inability to meet obligations: frequent coups, border disputes and mutual mistrust, together with the failure of some members to pay their financial dues and the poor transport and communication network, weaken the pace of integration.

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(a) Examples of rocks

• Sedimentary rocks: limestone, sandstone, shale, coal (any two).
• Metamorphic rocks: marble, slate, gneiss, quartzite, schist (any two).

(b) Four differences between sedimentary and metamorphic rocks

Additional difference: sedimentary rocks form at or near the surface at low temperature, while metamorphic rocks form deep within the crust under intense heat and pressure.

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(a) Four differences between lines of longitude and lines of latitude

(b) Straight-line distance between Tema (6 degrees N) and London (52 degrees N)

Both places lie on (or near) the same meridian, so the distance is measured along a line of longitude. The difference in latitude is:

Along a meridian, 1 degree of latitude = 111 km (approximately). Therefore:

The approximate straight-line distance is 5,106 km. (Using 110 km per degree gives \(46 \times 110 = 5{,}060\) km.)

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First set the data out clearly. Reading the table by year-column, the quantities (in kg) are:

(a) Total quantity of yams produced by the four states, 1995 to 1998

Add the four yearly totals: \[2{,}100{,}000 + 2{,}200{,}000 + 2{,}400{,}000 + 2{,}500{,}000 = 9{,}200{,}000\ \text{kg}.\] The total quantity produced during the period is 9,200,000 kg.

(b) Pie chart of the 1998 output

The 1998 total is \(600{,}000 + 700{,}000 + 800{,}000 + 400{,}000 = 2{,}500{,}000\) kg. Each state's angle is found from \[\theta = \frac{\text{state output}}{\text{total}} \times 360^{\circ}.\]

To draw it: construct a circle of convenient radius, mark a starting radius (12 o'clock), and use a protractor to mark off the angles in order, largest to smallest. Shade each sector differently, label it with the state and its value or percentage, and add a title and key.

(c) Two advantages of a pie chart

1. It shows clearly the proportion or share that each part contributes to the whole.
2. It gives an easy visual comparison between the sectors, so the largest and smallest producers are seen at a glance.

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(a)(i) Outline of the map reduced to one-third of the original scale

The extract is redrawn so that every length is reduced to one-third of its length on the original map, while the shape, orientation and relative positions of all features are kept exactly the same. The reduced outline, with the required features added for part (b), is shown below.

(a)(ii) Scale of the outline drawn

The original scale is 1:50,000, meaning 1 unit on the paper represents 50,000 units on the ground. When every distance on the paper is reduced to one-third, the same piece of ground is now shown by a paper length that is three times smaller, so each paper unit must represent three times as much ground:

The scale of the outline drawn is therefore 1:150,000 (that is, 1 cm on the outline represents 1.5 km on the ground).

(b) Features shown on the outline

The following are marked and named on the reduced outline above, each in its correct relative position taken from the extract:

• (i) The settlements of Okeigbo and Omifunfun, each shown by a small settlement circle and named. Okeigbo is drawn as a nodal point where several roads converge.
• (ii) The ridge east of Okeigbo, shown by its elongated pattern of closed contour lines running roughly north-south, with the crest marked.
• (iii) River Oni, drawn as a single line with an arrow indicating its direction of flow (from the higher ground in the north-east towards the lower ground in the south-west).
• (iv) The minor road from Idare to Omifunfun, drawn as a double broken line and labelled.

(c) Two reasons why Okeigbo could be considered more important than Mafoworade

1. Superior services and administrative functions: Okeigbo possesses a hospital, a district council office, a police station, schools and a piped water supply, whereas Mafoworade has none of these facilities. This concentration of social and administrative services makes Okeigbo a higher-order central place.
2. Greater accessibility as a nodal town: Okeigbo is a route centre where several roads meet, giving it far better accessibility for trade and movement of people and goods, while Mafoworade lies off the main route junctions and is far less accessible.

(d) Land-use types found in the area

• (i) Farming (agriculture): shown by the widespread areas of scattered cultivation across the mapped area.
• (ii) Transportation: shown by the presence of all categories of roads (main roads, minor roads and tracks) linking the settlements.
• (iii) Settlement: shown by the several settlements such as Okeigbo, Omifunfun and others, each performing different functions.

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(a) Two methods of irrigation agriculture in the Nile Valley

1. Basin (flood) irrigation: low earth banks divide the flood plain into large basins. During the annual flood, river water is led into the basins and allowed to stand for several weeks so that it soaks the soil and deposits fertile silt; the surplus is then drained back and crops are sown on the moist land. This is the older, traditional method.
2. Perennial (canal) irrigation: water is stored behind dams and barrages (for example the Aswan High Dam) and released all year through a network of canals to the fields. Water may be lifted onto the land by the shaduf, sakia (water wheel) or Archimedes screw, or nowadays by mechanical pumps and modern canal/sprinkler systems, allowing two or more crops a year.

(b) Three reasons for the development of irrigation agriculture in this region

1. The region has a hot desert climate with very low, unreliable rainfall, so farming is impossible without added water.
2. The Nile provides a permanent, dependable supply of water fed from distant rainy highlands, guaranteeing water even in the rainless valley.
3. The valley has fertile alluvial silt and a large population that must be fed, so intensive irrigated cropping (cotton, rice, sugar cane, cereals) is worthwhile.

(c) Four problems associated with irrigation agriculture in the Nile Valley

1. Salinisation and waterlogging of soils where drainage is poor and evaporation leaves salts behind.
2. Loss of natural silt fertility below the Aswan Dam, forcing farmers to buy expensive artificial fertilisers.
3. Spread of water-borne diseases such as bilharzia (schistosomiasis) and malaria that breed in the standing canal water.
4. Silting of canals and reservoirs, plus high cost of maintaining dams, pumps and canals, and pressure of population on the limited irrigated land.

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(a) Location on the outline map of Africa

• (i) Equatorial climatic zone: the Congo (Zaire) Basin and the Guinea coast lands lying roughly between 5°N and 5°S – town: Kisangani (or Douala).
• (ii) One Mediterranean zone: the extreme north-west coast (northern Morocco/Algeria) or the south-western tip around the Cape – town: Algiers (or Cape Town).
• (iii) Important town in each zone: as named above.

(b) Four characteristics of the equatorial climate

1. High temperatures all year, about 26 to 27°C, with a very small annual range because the sun is nearly overhead throughout.
2. Heavy rainfall all the year round, over 150 to 250cm, with no real dry season; rain is mainly convectional, falling as afternoon thunderstorms.
3. Very high relative humidity (about 80 per cent or more) and much cloud cover, giving a hot, sticky, oppressive feel.
4. Double rainfall maxima following the two equinoxes, and small diurnal (day-to-night) temperature range with regular "four o'clock" rains.

(c) Two ways the equatorial climate affects agriculture

1. The constant heat and moisture allow all-year cultivation of tree crops such as oil palm, cocoa, rubber and plantains, and support dense rainforest that yields timber; growth is rapid and continuous.
2. However, the heavy rain leaches nutrients and readily erodes bare soils, encourages rapid weed growth, pests and crop diseases, and the wetness makes drying and storage of harvests difficult, so shifting cultivation and careful soil management are needed.

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(a)(i) Two landforms produced by faulting

• Block mountain (horst).
• Rift valley (graben).

(Other examples: fault scarp, tilted block.)

(a)(ii) Characteristic features of a rift valley

A rift valley is a long, narrow trough of land that has sunk (subsided) between two roughly parallel faults. Its features are:

• It has a flat, sunken floor bordered by steep, parallel fault scarps (walls) on both sides.
• It is long and narrow, running for great distances (e.g. the East African Rift Valley).
• The floor often contains long, narrow lakes (e.g. Lakes Tanganyika, Nakuru) and sometimes volcanic activity.

(Alternatively, a block mountain/horst is an upstanding block bounded by fault scarps, with a fairly flat or dome-shaped top and steep sides, e.g. the Ruwenzori.)

(b) Importance of mountains to man

• They cause relief rainfall and are sources of rivers used for water supply, irrigation and hydro-electric power.
• They contain mineral resources and forests that provide timber.
• Their cooler, healthier climate and scenery attract settlement, farming and tourism (hill resorts).
• They serve as natural boundaries and defence barriers between regions or countries.
• Highland pastures support grazing of animals.

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(a) Four differences between local craft and heavy manufacturing industries

Other valid contrasts: craft industries need low or no power supply while heavy industries need large power supply; craft goods are hand-made while heavy-industry goods are mass produced.

(b) Three factors that have influenced the location of an iron and steel industry in Tropical Africa (for example Ajaokuta in Nigeria)

1. Availability of iron ore and other raw materials such as limestone and coal or nearby sources, reducing the cost of assembling bulky inputs.
2. Supply of power/energy from hydroelectricity, coal or natural gas needed to smelt the ore.
3. Good transport links (rail, road and water) to bring in raw materials and move out the heavy finished products.

Also acceptable: availability of water for cooling, capital and government policy, and a market for the steel.

(c) Three ways industrialization has contributed to the economy of Tropical African countries

• Employment creation: factories provide jobs, raising incomes and reducing unemployment.
• Earning of foreign exchange through the export of manufactured goods and saving of foreign exchange through import substitution.
• Development of infrastructure and growth of towns as roads, power and water supplies expand around industrial centres, and the government earns more revenue from taxes.

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