Answer:
Fires - These consume fuel and covert chemical energy stored in that fuel into thermal, light and sound energy
Decay - The breakdown of dead plants and animals produces thermal energy
Earth - Thermal energy comes from deep inside and is called geothermal energy
Explanation:
Fires, when you burn wood, you convert chemical energy from the wood into thermal (warmth from the fire), light (glow from the fire), sound (crackling sound of wood burning)
Decay - I can't explain that one to you but there are power plants that use decomposition to produce energy
Earth - Beneath the crust there is the mantle, which consists of molten rock which produces a lot of thermal energy. This can be seen in geysers, where the molten rock heats water and hot water can burst out of the surface. Applies to hot springs too
