411 students
Energy is the mode of life. It is essential for most human activities in modern...
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753 students
Soil pollution or contamination is largely caused by the presence of man-made chemicals or other...
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314 students
Water is a major component of our natural environment. Everything we do by way of...
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579 students
Disaster is a sudden adverse or unfortunate extreme event- natural or man-made, which causes great...
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