Answer:
They are often used as an energy source because they are found everywhere and because it has a high energy output. Fossil fuels can be found where an animal dies, coal is found, a tree is burned etc. This makes them highly popular and strived for. They also let off a high amount of energy when burned so it is used for automobiles,electricity, cooking and more.
Explanation:
If the allele frequency of a gene for brown fur is increasing from 15 to 25 percent, the population of the bears is evolving.
1. molecul of DNA 2. dna packed (coild) around histon h1 3.second stage of dna packing -solenoid thread 4. third stage of packing-chromosomal thread 5.chromosome-chromosomal threads are packed inside