Question
Write about the extraction of coal.
✓
Answer
About $300$ million years ago, the earth has dense forests in low lying wetland areas. Due to flooding, these forests get buried and compressed under the soil. The temperature also increases as they go deeper and deeper Due to the high pressure and temperature, dead plants slowly converted into coal.
Coal which is formed contains high carbon content, the slow process of conversion of dead remains into coal is called carbonisation.
Coal which is formed contains high carbon content, the slow process of conversion of dead remains into coal is called carbonisation.
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Word game: Use the clues to work out the words.
Across
3. Protruding voice box in boys
4. Glands without ducts
7. Endocrine gland attached to brain
8. Secretion of endocrine glands
9. Pancreatic hormone
10. Female hormone
Down
1. Male hormone
2. Secretes thyroxine
3. Another term for teenage
5. Hormone reaches here through blood stream
6. Voice box
7. Term for changes at adolescence
Across
3. Protruding voice box in boys
4. Glands without ducts
7. Endocrine gland attached to brain
8. Secretion of endocrine glands
9. Pancreatic hormone
10. Female hormone
Down
1. Male hormone
2. Secretes thyroxine
3. Another term for teenage
5. Hormone reaches here through blood stream
6. Voice box
7. Term for changes at adolescence