Answer:
combusting coal, oil and gas. Researches are looking in to diverse methods of harvesting energy to reduce the stress on oil and gas as existing wells of these natural resources, especially oil are emptying fast. New sources found for oil deposit are mostly very deep underground and difficult to be extracted. For this, higher end technologies for drills and more skilled engineers are needed. Both of these increase the cost to obtain oil for oil companies (Mae 2014). As crude oil sources are diminishing
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