JAMB UTME - Geography - 1991

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One of the consequences of the global increase in the carbon dioxide content of the atmosphere is the destruction of the ozone layer. Carbon dioxide is a greenhouse gas that traps heat in the earth's atmosphere, leading to global warming. As the concentration of carbon dioxide in the atmosphere increases, so does the amount of heat that is trapped, leading to rising temperatures. This increase in temperature has several consequences, including the destruction of the ozone layer. The ozone layer is a protective layer in the earth's atmosphere that absorbs harmful ultraviolet (UV) radiation from the sun. When this layer is damaged, more UV radiation reaches the earth's surface, leading to increased rates of skin cancer, cataracts, and other health problems in humans, as well as damage to crops and marine ecosystems. While carbon dioxide is not directly responsible for the destruction of the ozone layer, it contributes to climate change, which in turn can lead to ozone depletion. Other factors, such as the release of chlorofluorocarbons (CFCs) and other ozone-depleting substances, also play a role in the destruction of the ozone layer. Overall, the increase in carbon dioxide in the atmosphere has a range of consequences, including global warming and the destruction of the ozone layer.

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The longitudinal extent of Nigeria is 120 i.e. 30W and 150W
= 150W - 30W
= 120

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Nimbostratus clouds are commonly associated with continuous precipitation. Nimbostratus clouds are low-lying, gray or dark clouds that usually cover the entire sky. These clouds are formed when warm, moist air rises and cools as it meets a colder air mass. The cooling causes the water droplets in the air to condense and form a cloud. Nimbostratus clouds are often associated with steady, continuous precipitation, such as rain or snow, because they are thick enough to block out sunlight and their large size means they can contain a lot of moisture. In contrast, cumulus, stratus, and stratocumulus clouds are not usually associated with continuous precipitation. Cumulus clouds are fluffy and white and are often associated with fair weather, while stratus clouds are flat and featureless and are often associated with overcast or foggy conditions. Stratocumulus clouds are low, rounded clouds that often appear in rows and can be associated with light rain or drizzle, but not typically continuous precipitation.

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To determine the annual temperature range at the station, we need to subtract the minimum temperature from the maximum temperature. Looking at the table, we can see that the minimum temperature is -11oC and the maximum temperature is 19oC. So, the annual temperature range at the station is 19oC - (-11oC) = 30oC. Therefore, the answer is 30oC.

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The port terminals of the Atlantic-Far East sea routes are Hong Kong, Singapore, Manila, and Tokyo. These cities are all located in the Far East and are major ports for shipping and trade. Hong Kong is a major financial center and one of the busiest ports in the world, while Singapore is a global transportation hub and a key center for shipping and logistics. Manila is the capital of the Philippines and a major center for trade and commerce, while Tokyo is the capital of Japan and one of the largest cities in the world. Bombay, Colombo, London, Vancouver, Rotterdam, and Hamburg are not located in the Far East and are therefore not considered port terminals of the Atlantic-Far East sea routes.

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Climate is the least important factor in the location of industries. While climate can affect the comfort of workers and the transport of goods, it is not a critical factor in the location of industries. Power is necessary for running machines and equipment, market proximity affects the accessibility of goods to consumers, and raw materials are necessary for production. Therefore, industries are typically located near sources of power, markets, and raw materials. However, climate can still be a consideration, particularly in industries where temperature and humidity control is important, such as food processing or electronics manufacturing.

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The two major economic activities in the Chad Basin are fishing and irrigation agriculture. Fishing is an important economic activity in the Chad Basin, as the basin is home to a number of fish species such as tilapia, catfish, and carp. The fish caught in the basin are not only sold locally but also exported to neighboring countries, contributing significantly to the economy. Irrigation agriculture is another major economic activity in the Chad Basin. The basin has fertile soil, and with the help of irrigation, farmers are able to cultivate crops such as rice, maize, and sorghum. These crops are used for both domestic consumption and export, generating income for the region. Overall, fishing and irrigation agriculture are the two main economic activities in the Chad Basin, providing employment opportunities and contributing to the region's economic growth.

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The four basic components of the physical environment are: atmosphere, lithosphere, hydrosphere, and biosphere. 1. Atmosphere: It refers to the layer of gases that surround the Earth. It contains oxygen, nitrogen, carbon dioxide, and other gases that support life on Earth. The atmosphere also protects us from harmful solar radiation. 2. Lithosphere: It refers to the solid outermost layer of the Earth, which includes the crust and uppermost part of the mantle. It contains rocks, minerals, and soil that support plant and animal life. 3. Hydrosphere: It refers to all the water on Earth, including oceans, rivers, lakes, and groundwater. The hydrosphere provides a habitat for aquatic plants and animals and is an important source of food and water for humans. 4. Biosphere: It refers to all living organisms on Earth, including plants, animals, and microorganisms. The biosphere interacts with the other three components of the physical environment, as living organisms depend on the atmosphere, lithosphere, and hydrosphere for survival.

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Among the given options, Cuba has the least potential for the production of steel. This is due to various reasons such as lack of infrastructure, inadequate investment, and limited resources. Cuba does not have access to abundant and high-quality iron ore reserves, which are necessary for the production of steel. Additionally, the country's outdated machinery, limited access to modern technology, and insufficient skilled labor force further contribute to the low potential for steel production. Moreover, Cuba has been facing economic and trade sanctions, which have negatively impacted the growth and development of its industrial sector, including steel production. In contrast, countries like Japan, Germany, and India have well-established steel industries, abundant resources, modern technology, and skilled labor, making them more capable of producing steel.

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Water pollution can be caused by various human activities, such as sewage disposal, industrial effluent discharge, and increased silt load, which can lead to the contamination of water bodies such as rivers, lakes, and oceans. However, sand filling is not a cause of water pollution. Sand filling usually involves the use of sand to fill in a particular area of land or water, which can be done for land reclamation or construction purposes. While sand filling can impact aquatic ecosystems and habitats, it is not a direct cause of water pollution.

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The Ghezira Plains in Sudan is the place noted for irrigation agriculture in Africa. This region has a long history of irrigation dating back to ancient times and is renowned for its vast network of canals and irrigation systems. The area is characterized by a flat topography, abundant water resources from the Nile river, and a favorable climate that supports year-round cultivation of crops. The Ghezira Scheme, established in the early 20th century, is one of the largest and most successful irrigation projects in the world, covering over 8,800 square kilometers of land and producing a variety of crops including cotton, wheat, and sorghum.

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Rural-urban migration refers to the movement of people from rural areas to urban areas in search of better opportunities. One of the effects of this migration on the source region (i.e., the rural area) is rural depopulation. As people move to urban areas, the population of rural areas decreases, which can have several consequences. One consequence of rural depopulation is a decline in the rural economy. With fewer people living in rural areas, there is less demand for goods and services, which can lead to a decline in economic activity. This, in turn, can lead to rural unemployment as businesses close down or downsize. Another consequence of rural depopulation is a decrease in the quality of life for those who remain in rural areas. With fewer people living in rural areas, there may be less access to healthcare, education, and other services. Additionally, the loss of young and talented individuals to urban areas can limit the potential for growth and development in the rural region. Overall, rural depopulation is a significant effect of rural-urban migration on the source region. It can lead to a decline in the rural economy, rural unemployment, and a decrease in the quality of life for those who remain in rural areas.

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There are more settlements to the south because the terrain to the south is generally less rugged than the land to the north. Settlements tend to develop in areas that are more easily accessible and where it is easier to build infrastructure such as roads and buildings. The rugged terrain of the north can make it more difficult to build settlements and infrastructure, while the relatively flat terrain of the south is more conducive to human settlement. This is a common pattern of settlement in many parts of the world, where people tend to cluster in areas that are more easily accessible and habitable. The other options, such as the land to the north being more fertile, liable to flooding, or more prone to river blindness, may also affect settlement patterns to some extent, but the rugged terrain is likely the most significant factor in this case.

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The most important cash crop in the irrigated Nile Basin is cotton. Cotton is a major cash crop grown in many countries around the world, including the Nile Basin region, due to its economic value and versatility. It is widely grown in Egypt, Sudan, and Ethiopia, which are the main countries that make up the irrigated Nile Basin. Cotton is a significant source of income and employment for many people in these countries, as it is in high demand for use in textiles and clothing. The Nile Basin region's favorable climatic conditions, including ample sunshine and access to water, make it a suitable region for cotton cultivation. Additionally, the Nile River provides water for irrigation, making it possible to grow crops such as cotton in areas that would otherwise be unsuitable for farming. While other crops such as sugarcane, millet, and groundnuts are also grown in the region, cotton remains the most important cash crop due to its economic significance and cultural importance.

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The development of coal as a source of energy is relatively on the decline mainly due to the increasing availability and affordability of alternative sources of energy such as natural gas, wind, solar, and hydropower. Coal is also considered one of the dirtiest and most polluting sources of energy, contributing to air pollution and greenhouse gas emissions, which have harmful effects on the environment and human health. Therefore, many countries are transitioning towards cleaner and more sustainable sources of energy to mitigate the impacts of climate change and promote sustainable development. While the other factors such as the bulkiness and non-availability of coal may play a role in certain regions, they are not the primary reasons for the decline in the use of coal as a source of energy globally.

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Ocean currents are caused mainly by prevailing surface winds. Surface winds cause water to move horizontally across the ocean surface, creating currents. These winds are influenced by a range of factors, including the rotation of the earth, the shape of the continents, and the distribution of land and sea. The rotation of the earth also plays a role in ocean currents, as it creates a force known as the Coriolis effect. This effect causes the direction of the wind and currents to curve to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. However, prevailing surface winds are the main driver of ocean currents. These winds are created by differences in air pressure in the atmosphere, which in turn are caused by the heating and cooling of the earth's surface. The movement of these surface winds, along with the Coriolis effect, creates a circular pattern of ocean currents known as a gyre. While the amount of evaporation from the oceans and the shape of the ocean can also influence ocean currents, they are not the main causes. Evaporation can lead to the formation of denser, saltier water, which can sink and create vertical currents, while the shape of the ocean can create areas of upwelling and downwelling. However, these processes are secondary to the role of surface winds in driving ocean currents.

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Lateralization of soil refers to the process where different layers or horizons of soil develop in a lateral or horizontal arrangement, as opposed to a vertical one. This usually occurs in regions with high temperatures and heavy rainfall, leading to the leaching of minerals and nutrients from the upper layers of the soil. Therefore, the answer to the question is the tropical region, which is known for its high temperatures and heavy rainfall, making it an ideal environment for the lateralization of soil to occur.

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The major raw material needed in the iron and steel industry is limestone. This is because limestone is used as a flux in the process of making iron and steel. During the process, limestone combines with impurities in the iron ore to form slag, which can be easily removed. In addition, limestone is also used as a source of calcium, which is an important component in the production of steel. Therefore, limestone is an essential ingredient in the production of iron and steel.

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capillary refers to the degree of power to retain water. It?s not parts of the way of defining soil.

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The set of economic activities that is completely primary is fishing, lumbering, farming, and mining, as they are all considered primary economic activities. Primary economic activities involve the extraction and production of raw materials from natural resources, such as land, water, and minerals. Fishing involves catching fish and other seafood from oceans, rivers, and lakes. Lumbering involves cutting down trees for wood and paper products. Farming involves cultivating crops and raising livestock for food and other products. Finally, mining involves extracting minerals and other valuable resources from the earth. In contrast, transportation and manufacturing are considered secondary economic activities as they involve the processing, refining, and manufacturing of raw materials into finished products. Banking and trading are considered tertiary economic activities as they involve the exchange of goods and services rather than the production of raw materials.

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The two major air masses affecting the climate of West Africa are the tropical continental and the tropical maritime air masses. The tropical continental air mass is dry and hot, originating from the Sahara desert and brings dry and hot conditions to West Africa. On the other hand, the tropical maritime air mass is moist and humid, originating from the Atlantic Ocean and brings moist and humid conditions to the region. These two air masses interact to produce the distinct wet and dry seasons in West Africa. The wet season is dominated by the tropical maritime air mass, while the dry season is dominated by the tropical continental air mass.

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The two main determinants of the spatial distribution of agricultural crops in Nigeria are climate and soil. Climate refers to the long-term weather conditions of a region, including factors such as temperature, rainfall, and humidity. These climatic conditions have a significant impact on the growth and yield of crops. For instance, crops such as yam and maize thrive in regions with high rainfall, while crops such as sorghum and millet can withstand drought conditions. Soil is also a critical factor in the spatial distribution of crops in Nigeria. The type of soil in a region affects the availability of nutrients and water, which are essential for crop growth. For instance, crops such as cassava and cocoa require soils that are rich in organic matter, while crops such as cotton and groundnut require well-drained soils. Overall, the spatial distribution of crops in Nigeria is influenced by the climatic and soil conditions of a region. By understanding these factors, farmers can select crops that are best suited to the conditions in their region, leading to improved agricultural productivity and food security.

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The two areas of very sparse population in Nigeria are the Niger Delta and parts of Niger State, and Kano and parts of Borno State. The Niger Delta is a region in southern Nigeria where the Niger River empties into the Atlantic Ocean. It is sparsely populated because much of the land is covered by swamps and mangrove forests, making it difficult for people to live and farm there. Additionally, the region has experienced significant environmental degradation due to oil exploration and spills, which has led to a decline in agricultural productivity and forced many people to leave. Kano is a state in northern Nigeria that is also sparsely populated in some areas, as well as parts of Borno State. This is due to the region's arid and semi-arid climate, which makes it difficult for people to grow crops and raise livestock. Additionally, the area has been affected by conflict and insecurity in recent years, which has further reduced the population in some areas.

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The two most appropriate statistical diagrams that can be used to depict the data depend on the nature of the data being presented. Generally, a pie chart is suitable for showing how a whole is divided into its individual parts. It is a circular graph that is divided into sections or slices, each representing a proportion of the whole. Pie charts are useful for displaying data that consists of discrete categories or percentages. On the other hand, a bar graph is appropriate for showing comparisons between different categories or groups. A bar graph is a rectangular graph that uses bars or columns to represent each category or group's size or value. Bar graphs are useful for displaying data that can be measured quantitatively and is discrete, such as numerical values. Therefore, the two most appropriate statistical diagrams that can be used to depict the data depend on the type of data that is being presented. If the data consists of percentages or proportions, a pie chart is a suitable choice. However, if the data consists of numerical values or comparisons between categories, a bar graph is more appropriate. It's essential to choose the right type of graph that best represents the data and makes it easier for readers to understand the information being presented.

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The main source of tropical hardwood for timber is the rainforest. Rainforests are dense forests that receive high rainfall and are home to a wide variety of plant and animal species. Many tropical hardwoods come from these forests, such as teak, mahogany, and ebony. The timber from these trees is highly valued for its durability, strength, and beauty, and is used in a variety of applications, including furniture, flooring, and building construction. While other types of forests, such as montane forests and mangrove forests, may also contain hardwoods, the rainforest is the primary source of tropical hardwoods for timber.

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Shifting cultivation is an agricultural practice involving cultivating alternative plots to allow for natural regeneration. This practice involves clearing an area of forest or vegetation, planting crops for a few years until the soil becomes depleted, and then moving on to clear another area while the previous area regenerates naturally. This process is repeated over time, with farmers shifting from one plot to another, hence the name "shifting cultivation." It is commonly used in areas with low population density and is often a subsistence-based farming practice.

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To convert the time in New York to Baghdad, we need to take into account the time difference between the two locations. New York is in the Western Hemisphere and Baghdad is in the Eastern Hemisphere, so they are on opposite sides of the Prime Meridian (0° longitude). The time difference between New York and Baghdad is 9 hours, since Baghdad is 9 hours ahead of New York. Therefore, if the deadline in New York was 7 p.m. on 15th January, 1991, it would be 4 a.m. on 16th January, 1991 in Baghdad. To arrive at this answer, we need to add 9 hours to the time in New York to get the time in Baghdad. Thus, the correct answer is option D: 3 a.m. on 16th January.

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Fruits produced in the Mediterranean region of Africa are exported mainly to Western Europe because there is a higher demand for fruits in Western Europe than in Africa. In addition, there are better transportation facilities between Africa and Western Europe than within Africa, which makes it easier and more cost-effective to export the fruits to Europe. As a result, even though the fruits are produced in Africa, they are mainly consumed in Western Europe.

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The factor that is NOT an important factor in determining population distribution in a country or region is longitudinal location. Longitudinal location, which refers to the position of a place on the earth's east-west axis, is generally not a significant factor in population distribution because it does not directly affect the availability of resources or the ease of transportation. Factors such as industrial development, fertile soils for agriculture, and a well-developed transportation system are all important because they directly affect a region's ability to provide for its population and facilitate movement between different areas. Therefore, longitudinal location is not a major factor in determining population distribution in a country or region.

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To find the percentage of iron ore produced by the USSR in 1975, we need to divide the USSR's iron ore output by the total iron ore output of the five countries, and then multiply the result by 100 to get a percentage. The total iron ore output of the five countries is given as 333.590 thousand tonnes. So, the percentage of iron ore produced by the USSR is: (139.82 / 333.590) x 100 = 41.614% Therefore, the answer is 41.614%.

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The reason that BEST explains why African rivers are not very navigable is that most of the river courses are interrupted by rapids. Rapids are areas of a river where the water flows rapidly over rocks, causing turbulence and making navigation difficult or impossible. Since many African rivers have rapids along their courses, it makes navigation challenging and often dangerous. While low volume of water, short length of rivers, and seasonal rivers can also affect navigability to some extent, the presence of rapids is the main reason why African rivers are not very navigable.