8th Grade: How Much Do You Actually Know About Earth Science?

Boreholes are considered advantageous over hand dug wells because they reach the water table, making them a more reliable and cleaner source of water. This means that boreholes are able to access water from deeper underground, where it is less likely to be contaminated. Hand dug wells, on the other hand, may not reach the water table and are more susceptible to contamination from surface runoff and other pollutants. Therefore, boreholes provide a more secure and safer water source.

The correct answer is "There is no water available". This is not a problem with water supplies in LEDCs because the question is asking for a problem that is not present. The other options - lack of available clean water, diseases spread via the water supply, and water pollution - are all common problems faced by LEDCs in relation to their water supplies.

In MEDCs, the higher domestic use of water can be attributed to the popularity of labour-saving devices such as washing machines and dishwashers. These devices require a significant amount of water to operate efficiently, leading to increased water consumption in households. In LEDCs, where such devices are less prevalent, the domestic use of water is comparatively lower.

If toilets are not appropriately built or sited, they can contaminate wells and other water sources with raw sewage. This contamination can make the water unsafe for consumption or other uses, reducing the availability of fresh water in locations with no running water supplies. Therefore, providing appropriately built and sited toilets can help prevent this contamination and ensure the availability of clean and fresh water.

Borehole drilling to reach the water table is not a method of harvesting water because it involves extracting water from underground sources rather than collecting it from surface runoff or rainfall. Harvesting water typically refers to the collection and storage of surface water, such as rainwater or river water, for various purposes like irrigation or domestic use. Borehole drilling, on the other hand, is a method used to access groundwater for extraction through wells or boreholes.

Providing clean water benefits local populations in several ways. Firstly, it reduces disease and illness caused by contaminated water, improving overall health and well-being. Secondly, it increases the time available for work and education as people spend less time fetching water from distant sources. Thirdly, it reduces the cost of drinking water, making it more affordable for the local population. However, the statement "It allows local businesses to profit by selling clean water at high cost" is not a way that providing clean water benefits local populations. Instead, it suggests a potential negative impact where businesses exploit the need for clean water by charging high prices, potentially making it unaffordable for some individuals.

The correct answer is that the local population lacks the skills and tools to keep the systems repaired. This suggests that the charities may not have provided proper training or resources to the local community, leading to a lack of maintenance and eventual disrepair of the systems.

Wells can be a suitable source of water because they can be dug easily by hand. This means that even in areas without access to heavy machinery or equipment, wells can still be constructed to provide a source of water. This makes wells a practical and accessible option for obtaining water, especially in rural or remote areas where other sources may not be readily available.

Tied aid refers to a type of aid deal where conditions are attached that do not benefit the poorest sections of the population. In the case of the Pergau Dam project, the British Government agreed to provide aid to Malaysia, but with the condition that Malaysia purchased arms from Britain. This condition did not directly benefit the poorest sections of the population, as the aid was tied to a specific trade agreement rather than addressing their immediate needs for electricity and clean water.

Teaching farmers to use less water-intensive crops can help safeguard water supplies in poorer areas of LEDCs. By educating farmers on the benefits of planting crops that require less water, such as drought-resistant varieties or those with efficient irrigation techniques, the overall water consumption can be reduced. This approach promotes sustainable water management practices, conserves water resources, and ensures that water supplies are not depleted or overused in these areas.