Wood, when dry, stores chemical energy. This chemical energy is released as the wood burns, and it is converted into heat, or thermal energy. This also produces light energy. As a result of burning, the wood turns into an entirely new substance - ashes. Wood, a form of fuel with lots of potential energy stored in its covalent bonds, will react with molecules of oxygen in the air in a dramatic chemical reaction we call fire. The complex molecules in the wood have 'high energy' covalent bonds, as do the molecules of oxygen.
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D. the number of mates on the island
their appearance changes cause different birds breeding together can make an impact of how the bird looks
Oxygen, water, some type of resources to build, and food to eat