Answer:
A. They are extremely difficult to extinguish because fuel obviously is abundant and oxygen can enter easily, even through joints in surrounding rock.
Explanation:
Coal bed fires refers to spontaneous combustion which are triggered by human activity (mining), lightning, wildfires etc.
This usually happen underground when the coal beds are exposed to oxygen as a result of mining activities or human induced fires or combustion.
Answer:
Nanotechnology helps to improve viscous fingering and the nano-particles can transmit through nanopores of sandstone which helps to increase the recovery by decreasing the surface tension between oil and water. The pore spaces are very fine so water molecules cannot penetrate through all of them in order to push the oil. This is why the nano-particles such as iron (Fe) and Silicon (Si) are used with distilled water. These particles can easily move through the interconnected pores and thereby pushes the oil to move out of it. It is a widely accepted concept in Enhanced Oil Recovery (EOR).
Ethnic conflicts has been a contemporary concern