WAEC SSCE - Geography - 2007

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Seasonal changes in weather and climate are primarily caused by the revolution of the Earth around the Sun. The Earth takes approximately 365.25 days to complete one orbit around the Sun, which is known as a year. As the Earth orbits the Sun, it is tilted at an angle of approximately 23.5 degrees relative to the plane of its orbit. This means that different parts of the Earth receive different amounts of sunlight at different times of the year. When a particular hemisphere of the Earth is tilted towards the Sun, it receives more direct sunlight and experiences warmer temperatures. This is the season of summer in that hemisphere. Conversely, when that hemisphere is tilted away from the Sun, it receives less direct sunlight and experiences cooler temperatures. This is the season of winter in that hemisphere. The other two options listed, rotation of the Earth on its axis and the direct overhead sun on the Tropic of Cancer or Capricorn, do not directly cause seasonal changes. The rotation of the Earth on its axis causes the alternation of day and night, while the direct overhead sun on the Tropic of Cancer and Capricorn marks the solstices, which are the longest and shortest days of the year, respectively. However, these events do not directly cause changes in the seasons.

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The largest man-made lake in Africa is Lake Volta. Lake Volta is located in Ghana, West Africa, and was created by the construction of the Akosombo Dam on the Volta River. The lake covers an area of approximately 8,502 square kilometers (3,283 square miles) and has a maximum depth of 140 meters (460 feet). It is one of the largest reservoirs in the world by surface area and the largest man-made lake in Africa. The construction of the Akosombo Dam and the creation of Lake Volta had significant impacts on the local environment and communities. The dam provides hydroelectric power to Ghana and neighboring countries, but it also flooded large areas of land, displaced tens of thousands of people, and disrupted ecosystems and fisheries. In summary, Lake Volta is the largest man-made lake in Africa, created by the construction of the Akosombo Dam on the Volta River in Ghana.

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Zambia is a major producer of copper. Copper is a valuable metal used in many industries, including construction, electronics, and transportation. Zambia is one of the largest producers of copper in the world, accounting for a significant portion of global production. The country's copper production is primarily located in the Copperbelt region, which is home to some of the world's largest copper mines. The mining industry is a key contributor to Zambia's economy, with copper exports being a significant source of foreign exchange earnings. In contrast, Chad, Burundi, and Morocco are not major producers of copper. While these countries may have some copper deposits, their production levels are relatively small compared to that of Zambia. Therefore, the correct option is "Zambia."

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The characteristic of warm currents that is not mentioned in the options is that they flow from the polar regions to the equatorial region. Warm currents flow from the equatorial region towards the poles, carrying warm water from the tropics towards higher latitudes. This results in a warming effect on the regions they flow through, affecting both the climate and the oceanic ecosystem. Warm currents are also characterized by high surface temperatures due to the warm water they transport, and they tend to flow along the east coast of continents.

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The intrusive rocks are formed from the cooling and solidification of magma beneath the Earth's surface, whereas extrusive rocks are formed from the cooling and solidification of lava on the Earth's surface. Out of the given options, granite is an intrusive rock. Granite is a coarse-grained, igneous rock that is composed primarily of minerals like quartz, feldspar, and mica. It is formed by the slow cooling and solidification of magma deep beneath the Earth's surface, giving it a coarse texture and distinct mineral grains that are visible to the naked eye. In contrast, shale, sandstone, and marble are all sedimentary rocks that are formed from the accumulation and compaction of sediment or the recrystallization of existing rocks. Shale is formed from the accumulation of clay and silt-sized particles, sandstone from sand-sized particles, and marble from the recrystallization of limestone or dolomite. In summary, granite is the intrusive rock out of the given options. It is formed from the cooling and solidification of magma deep beneath the Earth's surface, giving it a coarse texture and distinct mineral grains. The other options are all sedimentary rocks that are formed from the accumulation and compaction of sediment or the recrystallization of existing rocks.

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The correct answer is "tilting of the earth on its axis." The tilt of the earth's axis does not necessarily prove that the earth is spherical in shape, as a similar tilt could also occur in a non-spherical shape. The other options listed provide evidence that the earth is spherical in shape: - The curved horizon of the earth: when looking at the horizon from a high altitude, such as from an airplane or a mountain, the curvature of the earth can be seen. This is because the surface of the earth curves away from the observer's line of sight. - The eclipse of the moon: during a lunar eclipse, the earth passes between the sun and the moon, casting a shadow on the moon's surface. The curved shape of the earth's shadow on the moon provides evidence of the earth's spherical shape. - Aerial photograph of the earth taken by astronauts: photographs taken from space show the earth as a spherical shape, as the entire surface of the earth can be seen from this vantage point.

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The area around the Equator is known as the Intertropical Convergence Zone (ITCZ) which is a belt of low pressure. The ITCZ is sometimes referred to as the doldrums because it is typically characterized by calm winds and sudden thunderstorms. The air in this area is heated by the sun, which causes it to rise and create a region of low pressure. As the air rises, it cools and the moisture in it condenses, leading to the formation of clouds and precipitation. This region is also characterized by high humidity due to the large amounts of moisture in the air. Therefore, the correct answer is the "doldrums", which is the area of low pressure around the Equator. It is an important area for shipping and navigation, as well as for the climate of the surrounding regions.

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Loess is not a metamorphic rock. Metamorphic rocks are formed from the transformation of existing rocks through heat, pressure, and chemical processes. Slate, marble, and gneiss are all examples of metamorphic rocks. Slate is formed from the metamorphism of shale or mudstone, marble from the metamorphism of limestone, and gneiss from the metamorphism of other rocks such as granite or schist. In contrast, loess is a type of sediment that is made up of fine-grained, windblown particles such as silt, sand, and clay. It is deposited in areas such as floodplains and desert basins and can be several meters thick. In summary, loess is not a metamorphic rock, while slate, marble, and gneiss are all examples of metamorphic rocks. Loess is a type of sediment that is deposited in areas such as floodplains and desert basins.

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A landlocked country is a country that is completely surrounded by land and has no direct access to the sea or ocean. China and South Africa are not landlocked countries as they have coastlines along the sea. Tunisia is not a landlocked country as it has a coastline along the Mediterranean Sea. Therefore, the answer is Burundi, which is a landlocked country located in East Africa. It is surrounded by Tanzania to the east and south, the Democratic Republic of the Congo to the west, and Rwanda to the north. Being landlocked can have economic implications for a country as it can limit trade and access to international markets.

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The answer is "inadequate workforce" because overpopulation usually results in an excess of labor supply, which can lead to unemployment, but not inadequate workforce. Inadequate workforce implies a shortage of people available to work, which is not a typical result of overpopulation. Overpopulation can lead to a rapid increase in population, which can cause various problems, such as the strain on resources, the decline in the standard of living, and the decline in the standard of health due to a lack of access to essential resources and services. Therefore, inadequate workforce is not a problem of overpopulation.

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Equal degree of cloudiness is represented by an isoneph chart. An isoneph chart is a map that shows areas of equal cloudiness. The term "isoneph" comes from the Greek words "isos," meaning equal, and "nephe," meaning cloud. On an isoneph chart, lines are drawn to connect points that have the same amount of cloud cover. For example, on an isoneph chart, areas with 50% cloud cover will be connected by a line, and areas with 70% cloud cover will be connected by another line. The lines allow meteorologists to easily identify areas of similar cloud cover, which can be helpful in predicting weather patterns. In summary, equal degree of cloudiness is represented by an isoneph chart, which is a map that shows areas of equal cloud cover by connecting points with the same amount of cloud cover with lines.

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The rocks at the core of the Earth are believed to be rich in iron and nickel. This is because scientists have studied the behavior of seismic waves passing through the Earth and have observed that they change their speed and direction when they encounter different materials. By analyzing these changes, scientists have determined that the Earth has a solid inner core and a liquid outer core. The outer core is thought to be composed of a mixture of molten iron and nickel, while the inner core is thought to be a solid ball of iron and nickel. This is supported by the fact that meteorites, which are believed to be remnants from the early solar system, also contain high amounts of iron and nickel.

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The Andes is not a mountain in Africa. The Atlas Mountains are located in North Africa, primarily in Morocco, Algeria, and Tunisia. The Tibesti Mountains are in the Sahara Desert and are located in the northern part of Chad and the southern part of Libya. The Rwenzori Mountains, also known as the "Mountains of the Moon," are located in the border region between Uganda and the Democratic Republic of the Congo. In contrast, the Andes is a mountain range located in South America, extending through seven countries from Venezuela in the north to Argentina and Chile in the south. In summary, the Andes is not a mountain in Africa. The Atlas Mountains, Tibesti Mountains, and Rwenzori Mountains are all located in Africa, while the Andes is a mountain range located in South America.

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The movement of the Earth around the Sun is known as revolution. The Earth takes approximately 365.25 days to complete one orbit or revolution around the Sun. This movement is responsible for the change in seasons and the different amounts of daylight and darkness throughout the year. It is important to note that revolution is different from rotation. Rotation refers to the Earth's spinning on its axis, which takes approximately 24 hours to complete one rotation. Rotation is responsible for the alternation of day and night. Orbit is another term used to describe the Earth's movement around the Sun, but it is not as commonly used as revolution. Evolution, on the other hand, is a term used to describe the gradual development or change of something over time, and is not related to the movement of the Earth around the Sun.

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The distance between Accra, latitude 5030N and latitude 51030N can be calculated using the formula: distance = 111.12 x difference in latitude. So, the difference in latitude is 51°30'N - 5°30'N = 46°. Substituting this value into the formula gives: distance = 111.12 x 46 = 5,107.52 km. Rounding up to the nearest whole number gives a distance of 5,108 km. Therefore, the answer is option D: 5,106 km.

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The relationship between the elements of an ecosystem is best described as interdependent. This means that the different living and non-living components of an ecosystem rely on each other to survive and thrive. For example, plants produce oxygen through photosynthesis, which is essential for the survival of animals that breathe oxygen. Similarly, animals provide nutrients for plants through their waste, which helps the plants grow. In this way, the different elements of an ecosystem are interconnected and rely on each other in a complex web of relationships.

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Density maps are most appropriate for showing the distribution of people in a place. A density map represents the density of a certain phenomenon, in this case, people, in a given area or region. The map shows the concentration of people in specific regions or areas, highlighting areas with high or low population density. Density maps are useful in understanding population distribution patterns and can help in analyzing trends, identifying areas of growth or decline, and making informed decisions related to urban planning, resource allocation, and social and economic development.

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A levee is a feature of river deposition. When a river floods, it carries sediment with it and deposits it on the surrounding floodplain. Over time, this sediment builds up and forms a raised bank or ridge called a levee. The size and height of the levee depend on the amount and type of sediment deposited by the river. Levees can help to contain future floods by restricting the river's flow and preventing it from spilling over onto the surrounding land.

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The correct answer is option A: I and III only. Rift valleys are formed due to tensional forces in the Earth's crust which pull the crust apart, causing it to stretch and thin. This leads to the formation of a depression or a valley, which is further deepened by erosion and other geological processes. Lateral forces and compressional forces, on the other hand, result in the formation of folds, mountains, and other geological features. The subsidence of the rift valley floor occurs after the valley has been formed, as a result of the continued movement of the Earth's crust.

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The instrument used for measuring relative humidity is called a hygrometer. A hygrometer is a device that measures the amount of moisture or water vapor in the air. It is an important instrument used in meteorology to help understand and predict weather patterns. The two common types of hygrometers are the mechanical and electronic hygrometers. The mechanical hygrometer uses a human hair or a piece of organic material that changes length in response to humidity changes. The electronic hygrometer, on the other hand, uses sensors to measure humidity levels and displays the readings on a screen.

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Humidity refers to the amount of water vapour in the air. When water evaporates from bodies of water or moist surfaces, it turns into water vapour and mixes with the air. The amount of water vapour that air can hold depends on its temperature and pressure. Warm air can hold more water vapour than cold air. When the air is saturated with water vapour, any additional water vapour will condense into tiny water droplets and form clouds, mist or fog. So, humidity is not the same as cloud cover or mist, but rather the amount of water vapour present in the air.

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The correct answer is option D: "on-shore movement of cold air". This is because cold air is denser than warm air, and as such, it tends to move towards areas of lower pressure. In Africa, the areas of low pressure are typically associated with the Inter-Tropical Convergence Zone (ITCZ), which is a belt of low pressure that circles the Earth near the Equator. The movement of the ITCZ, the convectional nature of hot tropical air, and the movement of moist air masses over higher ground are all factors that contribute to rainfall in Africa. However, the on-shore movement of cold air is not a significant factor in rainfall patterns in Africa.

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Africa's exploitation of solar energy will not result in less amount of solar energy received by plants for photosynthesis. This is because solar energy is harnessed by installing solar panels or solar collectors which do not reduce the amount of solar energy reaching plants. The other options are all potential benefits of exploiting solar energy in Africa. It can result in savings in liquid fuel and electricity costs as solar energy can be used as an alternative to traditional energy sources. Additionally, it can reduce the use of fuel wood, which can help to prevent deforestation and environmental degradation.

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Nairobi is not a capital city of an ECOWAS state. Nairobi is the capital city of Kenya, which is not a member state of ECOWAS. ECOWAS stands for Economic Community of West African States, and its member states are located in West Africa. The other options given in the question - Lome, Dakar, and Bissau - are all capital cities of ECOWAS member states, which are Togo, Senegal, and Guinea-Bissau, respectively.

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Convectional rains are most common in equatorial regions and tropical monsoon climates. Convectional rainfall occurs when the sun heats the ground, causing air to rise and cool. As the air rises, it cools and condenses, forming clouds. Eventually, the clouds become so full of moisture that they release rain. Equatorial regions and tropical monsoon climates are characterized by high temperatures and humidity, which create ideal conditions for convectional rainfall. The warm, moist air rises quickly, forming cumulus clouds that can develop into thunderstorms. These regions also experience a lot of sunshine, which helps to heat the ground and create the conditions for convectional rainfall. In contrast, polar regions and Mediterranean climates are not as conducive to convectional rainfall because they are generally cooler and drier. Temperate regions may experience convectional rainfall in the summer months when temperatures are warmer, but it is not as common as in equatorial regions and tropical monsoon climates. In summary, convectional rains are most common in equatorial regions and tropical monsoon climates because these regions have high temperatures, humidity, and abundant sunshine, which create the ideal conditions for convectional rainfall to occur.

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Chemical weathering is a process by which rocks are broken down and transformed into new substances through chemical reactions. This process is most effective in hot and wet environments. In hot and wet environments, chemical weathering is facilitated by the high temperatures and the presence of water. The heat provides energy for chemical reactions to occur, while water acts as a solvent, carrying and reacting with minerals within rocks. This process can lead to the breakdown of minerals, the release of nutrients, and the formation of new minerals that are more stable in the environment. In contrast, cold and dry environments do not provide enough energy for chemical reactions to occur quickly, and water is often limited, which can slow down the process of chemical weathering. Similarly, while warm and dry environments can provide energy for chemical reactions, the lack of water can limit the effectiveness of the process. Therefore, the most effective environment for chemical weathering is hot and wet, as it provides both the necessary energy and water to facilitate the breakdown and transformation of rocks through chemical reactions.

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The dominant climatic elements that control soil development are temperature and precipitation. Temperature affects the rate of chemical reactions that break down rocks and minerals, which form the basis of soil. High temperatures speed up these reactions, while low temperatures slow them down. Precipitation, on the other hand, affects the amount of water available to weather rocks and minerals, and to transport the resulting soil particles. It also affects the leaching of nutrients from the soil. In areas with high precipitation, there may be more leaching of nutrients from the soil, leading to nutrient-poor soils. Together, temperature and precipitation determine the rate of weathering, erosion, and soil formation. In areas with high temperatures and low precipitation, soil development may be slow due to limited water availability. Conversely, in areas with high precipitation and moderate temperatures, soil development may be rapid, but the soil may be nutrient-poor due to leaching. In summary, temperature and precipitation are the two dominant climatic elements that control soil development, with temperature affecting the rate of chemical reactions and precipitation affecting water availability and nutrient leaching.

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The instrument used for measuring atmospheric pressure is a barometer. A barometer is an instrument that measures atmospheric pressure, which is the force exerted by the weight of the atmosphere on the Earth's surface. The most common type of barometer is the mercury barometer, which consists of a glass tube that is closed at one end and filled with mercury. The tube is then turned upside down and inserted into a container of mercury, which allows the mercury in the tube to settle at a certain height. The height of the mercury in the tube is directly proportional to the atmospheric pressure, with higher pressure pushing the mercury up the tube and lower pressure allowing the mercury to fall. The atmospheric pressure can be read by measuring the height of the mercury column in the tube against a scale. Other types of barometers include aneroid barometers, which use a flexible metal chamber to measure changes in atmospheric pressure, and digital barometers, which use electronic sensors to measure pressure changes. In summary, a barometer is the instrument used for measuring atmospheric pressure. The most common type is the mercury barometer, which measures the height of a column of mercury in a tube to determine the atmospheric pressure.

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The Sahel savanna vegetation is predominantly found in Mauritania. The Sahel is a transitional zone between the Sahara desert to the north and the Sudanian savanna to the south. Mauritania is located in the western part of the Sahel region and has a semi-arid climate, which is characterized by low and erratic rainfall. The vegetation in this region is adapted to these conditions, with grasses and shrubs being the dominant plant types.

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The largest off-shore island in Africa is the island of Madagascar. It is located off the east coast of Africa in the Indian Ocean and is the fourth largest island in the world. The island is home to a diverse range of plants and animals, many of which are found nowhere else in the world. Madagascar has a rich cultural heritage, with a mix of African, Asian and European influences. The island is known for its unique wildlife, stunning landscapes, and beautiful beaches, making it a popular tourist destination.

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A fog is most likely to develop when a warm moist wind blows over a cold current. Fog is a type of low-lying cloud that forms when the air near the ground cools and reaches its dew point, causing water vapor to condense into tiny water droplets. In order for fog to form, there needs to be moisture in the air and a cooling mechanism. When a warm moist wind blows over a cold current, the warm air is cooled by the cold water below. This cooling process can cause the air to reach its dew point and form fog. This type of fog is called advection fog and is commonly seen near coastal areas where warm ocean currents flow over cold water. In contrast, when a cold dry wind blows over a cold current, there is little moisture in the air to form fog. Similarly, when a cold dry wind blows over a warm current or a warm moist wind blows over a warm current, the air is not cooled enough to reach its dew point and form fog. In summary, a fog is most likely to develop when a warm moist wind blows over a cold current because the warm air is cooled by the cold water below, causing the air to reach its dew point and form fog.

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During the equinoxes, day and night are equal in length for all places throughout the world. The equinox is a time when the sun is directly above the equator, and as a result, the length of day and night is roughly equal at all points on the Earth's surface. This occurs twice a year, around March 20-21 and September 22-23. Therefore, is the correct answer.

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