fossil fuel

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  1. 4. is combustible black or brownish sedimentary rock, formed as rtrato coall seams.
  2. 6. to as brown coal, is a soft,trown, combustible,sedimentary rock formed from naturally compressed peat.
  3. 7. fuel is a hydrocarbon-containg material formed underground from the remains of dead plants and animals that humans extract and burm to release energy for use.
  4. 9. is o raturally occurring petroleum product composed of narocardoh deposits and other organic materials.
  5. 10. a liquid which occurs naturally in rock formations
  6. 12. oil is o patral, occurring petroleum product Composed of hdrocarton depsits and other organic materials.
Down
  1. 1. coal is alower grade of coal that contains 35-45% carobn. The properties of are betweeh those of lighite, lowest grade of coal,and those of bituminous coal
  2. 2. gaus ( also called fossil gas somet imes just gos is a maturall occurring hydrocarbon gas mixture commonly includes various amounts of other higher alkanes.
  3. 3. fuels such as coal,petroleum, and natural gas are described as a special type of economic depsit.
  4. 5. known as hard coal and black coal,is a hard compact variety of coal that has a submetallic luster
  5. 8. coal,or black cod, is a type of coal containing a tar-like substance called bitumen or asphalt
  6. 11. is the surface organit layer of a soil that consists of partially decomposed organic matter, derved mostly form plant materially.